Team Venture comprises the central characters in the show; they live in a fortified compound in or near Colorado Springs, Colorado in the United States. The compound doubles as the headquarters for the company, "Venture Industries".

Dr. Thaddeus S. "Rusty" Venture (voiced by James Urbaniak): Dean and Hank's Father. He constantly lives in the shadow of his famous father Dr. Jonas Venture Sr., from whom he inherited Venture Industries. There is some question as to his actual degree of ability in the nebulously defined field of super-science. In fact, in "The Incredible Mr. Brisby", amusement park tycoon Roy Brisby accuses Dr. Venture of not having a doctorate at all. While Dr. Venture desperately wishes to emerge from his father's shadow, ultimately his knack for cutting corners proves his undoing, with his shoddy attempts at genuine technological innovation typically resulting in utter debacle (serving as the premise for several episodes), though some episodes such as the show's pilot and "Guess Who's Coming to State Dinner?" show that he is quite a capable inventor when it comes to the field of military hardware, producing nigh-indestructable personal force fields that can last for decades and mass-produced suicide bomber zombies that have netted him lucrative military contracts that have kept his lights on even when his more practical inventions fail. Dr. Venture is also shown to have an encyclopedic knowledge of supervillain cliches due to his childhood, using them to his advantage to escape many deathtraps thanks to Guild by-laws explicitly requiring that said cliches be adhered to. Dr. Venture is shown to have attended college with Brock, Pete White, Baron Underbheit and The Monarch, but he never graduated, apparently receiving "honorary degrees" from several Tijuana community colleges. Dr. Venture seems to dislike his son Hank; it seems ambiguous whether he actually cares for him at all. However, in Season 4 it is revealed that Dr. Venture sees a lot of himself in Hank and in fact, loves his son, but he feels that Hank is "cursed" in a way similar to himself, even stating that he sometimes feels that he should apologize to his son for conceiving him; his seeming preference for Dean was revealed to be because, while Dean is trapped in the world of super-science (having inherited his grandfather's scientific abilities) and thus must be prepared for what his life will be like, Hank has a chance to escape it and lead a relatively normal life. His sons have died on multiple occasions, but he has always replaced them, though each of their deaths is shown to have weighed heavily on his subconscious. His childhood with the original team Venture has had an undeniably traumatizing effect on him, and he still wakes up at night with nightmares of his most horrific adventures. Despite his issues, the episode "Self-Medication" shows that Rusty is much more stable in comparison to other former boy adventurers, who are shown to mostly spend their time wallowing in their wasted childhoods and resentment towards their parental figures. He takes pills to manage his erratic psyche, hallucinations, and stress.

Brock Fitzgerald Samson (voiced by Patrick Warburton): Brock Samson is a one-half Swedish, one-quarter Polish, one-quarter Winnebago "murder machine" who loves Led Zeppelin and recently acted as bodyguard to the Venture Family. For most of the series he has long blonde hair that is commonly remarked upon by others, often in reference to the biblical Samson. He was born in Omaha, Nebraska to a single mother. After being kicked out of college, he joined the US Army before joining the Office of Secret Intelligence (presumably a covert branch of the United States Government). There he acquired secret agent skills and a License to Kill. Even though Brock possesses a license to kill, he refuses to use a gun and instead wields a Ka-Bar fighting knife as his signature weapon. He relies on brute strength, endurance, and skill with a knife that borders on the supernatural. He is also able to tell whenever someone is in his car, apparently from an entirely separate continent, which Shoreleave believes is "a legitimate super-power". Brock also has subtly shown signs of being somewhat conflicted with his place in the world and unsure about his purpose as killing machine, such as when he confessed remorse for his murder of one Monarch henchman who later was revived by Dr. Venture into "Venturestein". Samson also has a personal code or ethics regarding innocents and whom he will kill if they are a threat to him and or the Ventures. In the season 3 finale, Brock becomes disillusioned with the O.S.I. and leaves the organization, also quitting his position as the Ventures' bodyguard. He then joins S.P.H.I.N.X., a group of other disillusioned O.S.I. agents who got tired of the rules and regulations put in place on the organization, and continues to keep a close eye on the Venture family (as S.P.H.I.N.X. uses an abandoned building on the Venture Compound for their base). In the season 4 finale, "Operation: P.R.O.M.", Brock and the other former O.S.I. members rejoins O.S.I. after Hunter Gathers is re-instated into the organization as its new commander. In season 6 he is reinstated by the O.S.I. as the Venture family bodyguard when they move to New York City. Brock also appears as a character in the crossover video game Poker Night 2. In Poker Night 2, though a conversation led by Brock and Ash from the Evil Dead franchise, GLaDOS from Portal finds out that Ash has a family relationship with Brock, as Ash is technically one of Brock's 14th century ancestors due to time travel. Also in Poker Night 2 his middle name is Fitzgerald according to GLaDOS

Henry Allen "Hank" Venture (voiced by Christopher McCulloch): A teenage boy, one half of the eponymous pair, a fraternal twin with blond hair. Hank's character is based on Joe Hardy of the Hardy Boys, Jonny Quest, and Fred Jones of Scooby-Doo. He tends to be more athletic and better at disguises than his brother. He is shown as the more outgoing and daring of the pair, and more attracted to adventure. In season 4, he became more rebellious when Brock had left, even going so far as to lose his virginity (nearly all knowledge of this event has been erased from his memory, however). Like his brother, Hank has been killed over a dozen times, but replaced with an exact clone who is supposed to have no memory of his own deaths; though he vaguely recollects jumping off the roof of his house in a Batman costume. After briefly joining the former Henchman 21's version of S.P.H.I.N.X. in season 5, Hank attained the power suit of former villainous S.P.H.I.N.X. member The Countess, which he wore until it was stolen by Molotov Cocktease in a fight and then destroyed by Brock Samson, leaving Hank in physical therapy for some time due to his atrophied muscles. In the end of season 5, Dean reveals to him that the two are clones of their original selves, but this does not upset him, and his own optimism about his previous technical immortality raises Dean's spirits. In season 6, Hank decides to forgo college and gets a job at a pizzeria as a delivery boy. He also begins a relationship with Sirena Ong, the daughter of his father's current Guild-assigned villain.

Dean Venture (voiced by Michael Sinterniklaas): A teenage boy, one half of the eponymous pair, a fraternal twin with red hair. Dean is timid, selfless, and more "bookish" than Hank. He is a combination of Frank Hardy, Peter Parker (in fact, he wears Spider-Man pajamas in several episodes) and stereotypes of boys from the 1950s (e.g. Henry Huggins, Buddy Holly). While more timid than Hank, he shows signs of being slightly less emotionally stunted than his brother, as he has a crush on Triana Orpheus. Dean is considered the "smart" son by Rusty. Dean has been killed over a dozen times, but each time he is replaced with an exact clone who has no memory of the death. He is named after fantasy artist Roger Dean, who made the cover art for some of the records in his and his father's progressive rock album collection. He is an avid reader of the Giant Boy Detective series of books. After being dumped by Triana in the season 4 finale, Dean has become more of an emo, dressing in a black "speedsuit", moving out of his childhood bedroom, and becoming more sarcastic and unwilling to go with his father and brother on adventures. In "A Very Venture Halloween", Dean discovered that he and Hank were clones, a fact that he found disturbing and extremely upsetting. He responded by further distancing himself from his family. Since the season 5 premiere, Dean has become far more cynical; he has begun to use stronger language and now actively hates Triana for not only breaking up with him, but for dating someone else (he freely admits that he does not care if she is happy, only if he is). In the season 5 finale, he reveals the truth about their existence to Hank, who responds optimistically and changes Dean's outlook on their lives and allows him to move on from Triana and his self-pity. In season 6, Dean begins attending college in New York, where he thrives as a student of philosophy and finally finds a friend in Brown Widow.

H.E.L.P.eR. (voiced by "Soul-Bot"): The Venture family's personal helper robot. H.E.L.P.eR. is an acronym for Humanoid Electric Lab Partner Robot. He was created by Dr. Jonas Venture Sr. to look after his son Rusty, but now assists Brock in looking after Dean and Hank. H.E.L.P.eR.'s role as an assistant to the Venture family is often reminiscent of Alfred Pennyworth, lifelong butler of Batman. H.E.L.P.eR. does not speak, but rather communicates via electronic beeps that are more or less understood by the Venture clan, similar in many ways to R2-D2. Though he is very sensitive, the Ventures often treat him like an old appliance or pet. The robot routinely gets smashed to pieces during the course of their adventures, but seems to get repaired by the next show. At the end of Season 3, he was destroyed in a car accident with 24. In Season 4, it was revealed that his head was lodged into Brock's chest, where he was later removed and fused with the Walking Eye. In the opening episode of season 5, it is revealed he was sold to Augustus St. Cloud but Billy Quizboy rescues him after beating St. Cloud in a trivia game. In the following episode, "Venture Libre", Dean restores H.E.L.P.eR. to his original body.

Sergeant Hatred AKA Courtney Robert Haine [1] (voiced by Brendon Small in season 2 and Christopher McCulloch from season 3 onward): Brock's former supervisor in the O.S.I., Dr. Venture's new one-time nemesis and, as of season 4, the family's bodyguard. Hatred becomes Venture's nemesis after The Monarch's forced departure from that position. Hatred is a large man with a giant red 'H' tattooed on his face (the rest of the word "hatred" is tattooed vertically down his body) and wears military fatigues much like the Marvel villain Nuke. He was The Monarch's next door neighbor when The Monarch had moved into Phantom Limb's former house. Sergeant Hatred mentions at a party that he hosts that he cannot be within 50 feet of a minor due to a court order, though he is married to Princess Tinyfeet and has a foot fetish. Despite being a convicted child molester, he is liked and respected throughout the supervillain community for his unfailing politeness and generosity; certain episodes also reveal that he knows his sexual attraction to children (and young adolescents) is wrong, and tries to keep it in check, in part by self-administering the IV drug "Nomolestol". The Monarch's henchman, namely 21 and 24, routinely steal parts from Hatred's technology, using his hover tank to rebuild the cocoon. 21 steals jet-packs from him as well. Hatred briefly chose Dr. Venture as his arch-enemy as revenge on The Monarch for his years of theft, planning to make Venture's life wonderful but accidentally ends up rediscovering his empathy. As of season 4, Hatred has become the Ventures' new bodyguard and has rejoined the O.S.I. As of the Season 4 finale, Hatred had removed all of the word "Hatred" from his body, except for the D, which was placed in a "tender area". He had put a new tattoo on his face that is a giant V, for "Venture"; this causes Dr. Venture to sarcastically nickname him "Sergeant Vatred". During Season 4, Sgt. Hatred discovers his wife has left him for Captain Sunshine's archenemy Scorpio, and he falls into a depression. He also develops a case of gynecomastia in the Season 5 premiere due to a reaction between the Nomolestol and the Super Soldier serum he was injected with while with the O.S.I. and confesses to Dr. Venture that he likes to look at his enlarged breasts when he masturbates. His past in O.S.I. is further revealed as being the result of a super soldier program a la Captain America, but like in the comics, failed and Hatred ended up more like Nuke (a big muscular jarhead, relies on medication to balance out mental issues, etc.). However, while his physical prowess increased dramatically, his empathy disappeared, magnifying his pederastic tendencies to a violent level. In season 6 he is reassigned to a desk job from his mission as the Venture bodyguard and is replaced by Brock Samson, news he does not take well. Hatred ultimately gets around this order by taking a part-time job as a night security guard at the Venture Industries headquarters.

Dermott Fictel-Venture (voiced by Doc Hammer): An obnoxious teenager who first appears in "The Buddy System"; he was hinted to be the son of Brock Samson. Dermott is a compulsive liar and frequently interjects wild, and often clearly false claims about his abilities and past deeds into unrelated conversations. He is a friend of Hank's and occasionally visits the Venture compound from the nearby trailer park where he and his "mother" live. In the season 4 episode "Everybody Comes to Hank's" Hank sleeps with Nikki Fictel (voiced by Kate McKinnon) whom he knows as Dermott's older sister. It is revealed that Nikki is actually Dermott's biological mother and that her mother raised Dermott as her own son. When Nikki was 15 she had been the chairperson of the Rusty Venture Fan Club and she was impregnated by Rusty Venture, who was tricked into thinking she was 20. Rusty paid the family off with a check due to threats from Dermott's grandmother about pressing charges for statutory rape unless he did so, despite Venture wanting to take responsibility and raise the child with Nikki. This also means that Dermott is in fact the third Venture brother. In "From the Ladle to the Grave: The Story of Shallow Gravy", Dr. Venture has an interview in which he seems to believe Dermott is Brock's son. However, by the end it is implied that Dr. Venture has figured out that Dermott is his son, and whenever he is at the compound in season 5, Venture treats him as such without revealing it to him in order to make up for not being able to convince Nikki's mother to let him help raise Dermott. After discovering he can understand H.E.L.P.eR, Dermott discovers this as well when in the episode "Momma's Boys" when Doctor Orpheus rescues him and explains he is psychically connected to the Venture boys, resulting Dermott learning he is one of the Venture boys. He hints at this knowledge in the episode's post-credits scene, in which he calls Rusty "Dad" as he leaves the family's kitchen. He stays behind when the Venture family moves to New York and joins the OSI, being accepted as an operative despite his lack of training thanks to a good word put in for him by Dr. Venture.

Dr. Jonas Venture, Jr., also known as J.J. (voiced by James Urbaniak): Dr. Venture's deformed twin, who was absorbed by Rusty in the womb. Until the first-season finale, he appeared only in Dr. Venture's nightmares. He was freed from Rusty's body via surgery after being mistaken for a tumor. Desperate to claim the life that was stolen from him, he tried to murder Dr. Venture using a giant mechanical suit that he made out of household items. Though he has the body of an infant, his head has matured to an adult appearance and bears a striking resemblance to that of his father. He also seems to have inherited his father's brilliance, unlike Thaddeus, as he earned two doctorates within the period of a month (the amount of time Thaddeus had spent escaping his former life). By the end of the first season, Thaddeus has agreed to share his Venture birthright with his brother and the two eventually manage to find a measure of respect and care for each other. He is given the old Venture compound on Spider-Skull Island, as well as the X-2, the boat built by their father. Jonas Jr. begins a relationship with Sally Impossible. Jonas Jr. appears to be everything his brother is not: scientifically astute, hard-working, attractive to women, about two feet tall, and possessed of a full head of hair. At the same time, however, J.J. is shown to be utterly incompetent as a "protagonist" (the hero in a hero-villain relationship), not following proper procedure and flagrantly violating Guild and OSI rules, believing the entire business of arching to be a simple hobby that his family and their various enemies indulged in, leading to the disaster at the opening of his museum due to him inviting Scaramantula and Brainulo (who Jonas Sr. had stolen Spider-Skull Island from) to the occasion, as well as multiple other villains who carried a deep-seated grudge against his father. His detached hero worship of his father also causes the original Team Venture to greatly dislike him, as he totally ignores their importance to his father's life, business, and legacy. In season 5, he is shown to have been even more successful in his ventures, making a Gargantua-II and manufacturing and marketing the jPhone smartphones and the jPad tablet computers, however, it has been hinted that his relationship with Sally is on the rocks and his business is in danger due to his many extravagant pet projects. It is later revealed that J.J. made a deal with the Investors to receive his doctorates and for his business to be secretly financed by them (explaining his immediate success) in exchange for what is implied to be his own life and that he has contracted terminal cancer as a result of the Investors coming to collect what they are owed, something JJ attempted to prevent by apparently planning to steal his brother’s organs to save himself, though he eventually decided against it. JJ dies in the season 6 special "All This and Gargantua-2", sacrificing himself along with Treister in order to prevent the explosion of Gargantua-2 from hurting anyone. JJ later reappears as a hologram in season 6 and 7.

Triana Orpheus (voiced by Lisa Hammer): Dr. Orpheus's 17-year-old quasi-goth daughter. She has purple hair, and is fairly friendly with the Venture boys. She is possibly the most down-to-earth character on the show, despite her father's tendency to dramatize. She takes an interest in kitsch. In season four it is revealed that she has inherited her father's abilities when she encounters her father's mystical mentor who purposely took up residence in her closet as a result of her power. As of season four, she is living with her mother and stepfather, the Outrider, and has a boyfriend named Raven.

Pete White (voiced by Christopher McCulloch): An albino computer scientist and co-founder of Conjectural Technologies. He went to college with Venture, Samson, Baron Ünderbheit, and The Monarch where he hosted a new wave radio show called "The White Room". After college, White and Billy Quizboy worked in tandem on a Jeopardy-styled gameshow, called "QuizBoys" in which Pete hosted and Billy participated. After a debacle concerning the show seeding Billy's answer display with the correct answer, regardless of what he put down, White and Quizboy were fired and left to find new lives. While the two had a short falling out, Pete eventually rejoined Billy (after his short unwanted stint with O.S.I. and his task of spying on Phantom Limb). They find refuge in a trailer near the Venture Compound where they currently reside. Like Venture and Quizboy, White tends to be somewhat lazy and half-hearted in his efforts. On occasion, characters refer to him as "the gay albino", but he is heterosexual. Season six reveals that White has a doctorate in computer science, making him one of the few characters on the show with a doctorate they have actually earned.

William Whalen, a.k.a. Master Billy Quizboy (voiced by Doc Hammer): A self-proclaimed "boy genius," Billy Whalen is actually an adult (35 in "The Buddy System", 37 in "Handsome Ransom") with a speech impediment and growth hormone deficiency. He suffers from hydrocephalus, although his intellect seems to be unaffected by this condition. He starred as a contestant on the game show Quizboys hosted by Pete White. When White cheated for him (unknown to Billy), they were both kicked off the show and Billy's winnings were frozen by the SEC. White and Billy went to California where they were planning to work for Rusty Venture, however Rusty turned them both away. After this, Billy was accidentally entered into a dog fight, thinking it was an underground quiz match. Billy lost a hand and eye in the mix up. Billy left White, and was recruited by O.S.I. agents Brock Samson and Hunter Gathers, who provided him with a mechanical hand and camera eye. Brock and Hunter sent Billy undercover to spy on Professor Hamilton Fantomas and dig up dirt on the possible existence of the Guild of Calamitous Intent. Fantomas had Billy help with his experiment, but the experiment went wrong, Fantomas became Phantom Limb and Billy lost his left eye again. After a mind wipe, Brock (newly assigned to Venture) smuggled Billy out of O.S.I. and left him with White. He then became a neurogeneticist and co-founder of Conjectural Technologies. He is a virgin as revealed during a conversation with Pete White and Dr. Venture (until Monstroso purchased prostitutes for him, in exchange for open heart surgery in "The Silent Partners"). In "The Invisible Hand of Fate", Billy hits his head on a toilet and remembers everything. He also briefly joined the Order of the Triad in exchange for his performing brain surgery on the Outrider after claiming he should be paid for his endeavor. In season 5, Billy's old nemesis Augustus St. Cloud became his and White's designated arch-enemy, much to the duo's delight. Season 6 reveals that Billy registered himself and White with the O.S.I. as "Billy Quizboy and the Pink Pilgrim" and modified his cybernetic hand with new functions to fit his new Super Scientist lifestyle.

The Pirate Captain (real name unknown) (voiced by Christopher McCulloch): The leader of the "ghost pirates" in the episode "Ghosts of the Sargasso". After his initial encounter with the Venture family, he began living on the X-2 after having difficulties in finding a job. When Jonas Jr. acquired the ship, he hired the captain. He has not been referred to by any name or nickname other than "The Captain" so far. He resided with Jonas Jr. on Spider Skull Island and fulfilled the duties of a butler, caretaker, and right-hand man. The Captain always refers to Jonas as "Chairman". Later, after J.J.'s death aboard Gargantua-2, the Captain becomes an employee of Dr. Venture when he inherits J.J.'s business in New York City and relocates there. The Captain also struggles with a recurring traquilizer dart addiction.

Dr. Byron Orpheus (voiced by Steven Rattazzi): An expert necromancer and mystic who rents a portion of the Venture Compound and is friendly with Dr. Venture. Along with Brock, he is the only associate of Dr. Venture who displays any sort of competence, although his pomposity tends to detract from his abilities. His character is a parody of vintage comic book magic-users such as Doctor Strange and the even older Mandrake the Magician. His face and hair are similar to those of Vincent Price and Christopher Lee as Duc de Richleau (The Devil Rides Out). Orpheus only holds a bachelor's degree in communications, but claims he has received his doctorate from a "higher source." He has been confused for Dracula a number of times. His speech is filled with overly dramatic phrases, delivered in a theatrically grandiose voice with extreme emphasis on mundane topics, usually over a background of ominous trumpet-laden music, implying the pun, "Dr. Obvious". After witnessing Dr. Venture's various enemies, he develops a fervent desire for a nemesis of his own, and is later given the opportunity when the Guild approves his request for one in the season 2 episode "Fallen Arches", holding a series of interviews for the position. He is fiercely protective of Hank and Dean Venture, after being responsible for their "death" at the end of Season 1, only to find out the truth about the boys in Season 2.

Jefferson Twilight (voiced by Charles Parnell): An old friend of Dr. Orpheus. He is a black man who exclusively fights Blaculas (blackvampires) for a living and wields two swords. He is a pastiche of the superhero Blade and the blaxploitation movie protagonist Shaft with a voice very closely resembling Samuel L. Jackson. As a play on Blade's half-vampire thirst for blood or an artificial replacement, Jefferson Twilight suffers from diabetes and low blood-sugar, leading him to heavily thirst for sugared liquids, such as Nik-L-Nips. His left eye is discolored as it is a magical blacula tracker he calls the "Blood Eye." The episode "What Goes Down Must Come Up" reveals much of his back story, including that his mother was taken by marauding Blaculas when he was ten and he was a tank commander in the USMC.

The Alchemist (voiced by Dana Snyder): Another old friend of Dr. Orpheus, who is searching for the philosopher's stone ("as a metaphor for enlightenment") as well as a cure for AIDS. Unlike Twilight and Orpheus, it would seem that he is much less serious about his business and would rather mix business with pleasure; however, his true opinion on the Triad was revealed in the episode "Showdown at Cremation Creek", where he stated that he was more into helping the balance of the Universe than running around fighting one Super-Villain. It has been openly acknowledged that he is gay and a fan of Jimmy Buffett. He is also friends with Hank, as he feels the two of them are similar. He is sometimes referred to as "Al", but whether this is his real name or merely short for Alchemist is uncertain. He has an open hatred of the Internet due to finding out his previous boyfriend was cheating on him via MySpace. It is revealed in "Everybody Comes to Hank's" that he was previously in a relationship with Shore Leave, but that the latter erased his memory of it because The Alchemist had become too "clingy." In "OSI Love You", he and Shore Leave have an amorous video chat implying they got back together.

Dr. Jonas Venture, Sr. (voiced by Paul Boocock): Deceased father of Dr. Thaddeus Venture, Jonas Junior, and as of season 7, it's implied that he is also Malcom's aka "The Monarch's" father. Jonas is seen in dreams, hallucinations, old videotapes, and flashbacks. He was the foremost scientist and adventurer in the world of his time and every bit as careless with his son as Dr. Thaddeus Venture is with his children. He created what is now known as Venture Industries and led the original Team Venture. His character is based on Doc Savage and Dr. Benton Quest. In the episode entitled "ORB", it is implied that Kano killed Dr. Venture under orders from the O.S.I., in order to protect the secret of the mysterious ORB. His public reputation is excellent; he is generally viewed as a brilliant scientist, adventurer, and generally a wonderful man. The events of the show, however, have demonstrated that the truth is not as clear cut. In reality, Jonas was nothing more than an extremely sexist man-child, he seemed to be more concerned with having fun, typically letting others clean up the mess and do the leg work, and is apparently considered by the Guild to have been a greater villain than any of those he fought. He also seems to have considered Rusty as being a drag on his life (implying that Rusty was the result of an unplanned pregnancy), and took any chance he could to drink heavily, party, and hire prostitutes to entertain himself and his friends (even if this chance happened to be Rusty's birthday) and to generally ignore his son's existence. He also subjected Rusty to years of attempted emotional manipulation and abuse through "therapy" sessions which boiled down to Jonas repeatedly reiterating how "ungrateful" Rusty was, which eventually led to the two genuinely hating each other and barely speaking in the years leading up to Jonas's death. In "What Goes Down Must Come Up" the deranged computer system M.U.T.H.E.R attacks and he abandons a train full of orphans and never comes back for them, leading them to become secluded lunatics who ironically worship him. In "The Buddy System" he created a chamber to help astronauts live in space but simply forgot about it. Their fates are unknown but one of their skeletons was displayed ceremonially. His actions had a particularly damaging effect on his son, Rusty. In "Dr. Quymn, Medicine Woman" he is shown surreptitiously slipping his key to young Tara Quymn's mother behind the back of her husband, the closeted but enthusiastically bisexual Colonel Gentleman, at a key party Jonas was hosting. Later Jonas and Mrs. Quymn fall on the box fort in which Rusty and Tara are playing while wildly making love. In "The Incredible Mr. Brisby" it's shown he tested his inventions on Rusty when he was little. He is shown to have a haphazard style of parenting often ignoring his duties or delegating them on to others. In "The Doctor is Sin" he (inadvertently) exposes his genitals to Rusty, instilling in him a deep sense of insecurity and inadequacy. In "Careers in Science" he brought Rusty up to a space station to assist him, which Rusty later openly questions. In "Now Museum-Now You Don't" Dr. Venture remarks that his time in Team Venture traumatized him; in "Are You There, God? It's Me, Dean", The Monarch comments to Hank that Hank's grandfather "really did a number" on Hank's father. In the season 3 finale Dr. Venture mentions his dad made him kill a man with a house key. In the season 7 premiere, it is revealed that Jonas is actually still "alive" in the medical sense, having been reduced to a head and nervous system during the infamous "Movie Night" incident on Gargantua-1 and, in accordance with his contingency plan in such a case, he was entombed within the ProBLEM device on the station, which kept him in a state between life and death until the time came where he could be saved. The ProBLEM was found by JJ after the Gargantua-1 crashed and, unaware of its true purpose, placed it in the lobby of Ventech headquarters as a decorative piece. In Season 7, Episode 3, it is revealed in flashbacks that Dr Jonas filmed an orgy between him and the original Blue Morpho. Jonas then used the tape to blackmail the Morpho into doing his shady work. He always called the Morpho his "friend." The original Morpho may have been sterile, but Jonas convinced/tricked Morpho he could use "potent science" on his wife. Less than a year after Jonas' "examination" The Monarch (Malcom) was born. After the Morpho's plane goes down, in a true ego trip, Jonas turned the Morpho into a cyborg after his plane went down. After declaring it "The most amazing feat of super-science," Jonas quickly abandoned the cyborg after he "grew bored" according to the original Venture Team. The cyborg was able to interface with Jonas in the ProBLEM where all the flashbacks occur. In a vain attempt to save himself, Jonas tries convincing Billy to switch his brains with the Cyborg Morpho, but Billy refuses to kill him.

The Action Man, whose real name is Rodney (voiced by Christopher McCulloch): Retired member of the original Team Venture. He is an all-American supersoldier reminiscent of a B-grade Nick Fury, though his costume evokes elements of a vintage Captain America. Since his retirement, he has become a crotchety old man with flatulence problems and "plastic knees" that hinder his movements. He married Major Tom's widow, Jeannie, after Tom's tragic accident. When he starts to ask Dr. Orpheus a question, Dr. Orpheus interrupts with "Two years and seventeen days, by a stroke." to which he appears pleased. This was assumed to be referring to The Action Man's death. However, since he lives longer than that time and his wife dies of a stroke, and he eventually marries a woman he has been pursuing for decades, it may have referred to when his wife would die. The Action Man gets his name from the David Bowie song "Ashes to Ashes", which functioned as a follow-up to "Space Oddity", which introduced "Major Tom". Like Jonas, he wasn't well trained with children and was hinted to have had some bad moments with young Rusty. He had a habit of waking up Rusty Venture back in the old days by placing an unloaded gun against the sleeping boy's head and pulling the trigger, in which he said "not today, Rusty". According to Rose, Rodney was a womanizer and a junkie; which he both denied claiming it was all in the past and never cheated on Jeanie, which is most likely a lie. "Action Man" is also the name of Hasbro's original 12 Inch GI Joe figures, released outside the United States. The Action Man has since moved to a retirement community in Boca Raton, Florida, where he is alone following the death of Jeannie. He briefly had Dr. Entmann as a roommate, only to accidentally crush him with his rocking chair while Dr. Entmann was in a shrunken-down state. When taking care of Hank, he has the boy help him seduce fellow retiree Rose, later revealed to be Billy Quizboy's mother, and then moves in with Colonel Gentleman after giving Dr. Entmann a proper funeral.

Colonel Horace Gentleman (voiced by Christopher McCulloch impersonating Sean Connery): Retired member of the original Team Venture and later ersatz leader of the reformed Team Venture. He is a Scottish gentleman and adventurer in the vein of Allan Quatermain and James Bond. The influence is apparent in the similarity of his voice to that of Sean Connery, who has played both characters in movies. He dresses in an old-fashioned British suit, complete with cane and fedora. (His design is likely based on Theodore Marley "Ham" Brooks, a similarly up-classed, cane wielding gentleman who was one of Doc Savage's 'Fabulous Five'.) It is briefly implied that he is a pederast and this was later confirmed by the creators.[2] In the second season, Hank and Dean find him apparently dead of unspecified causes; however, it is revealed in the Season 3 episode "Now Museum-Now You Don't" that he was merely in a diabetic coma and is still alive. He is an ethnic/gender chauvinist, and has a penchant for writing out random lists in his notebook such as "Toys Colonel Gentleman Wishes He Had When He Was a Lad but They Weren't Invented Yet", "Good Name for An Imaginary Friend", and "Hollywood Actresses That Need a Smack in the Mouth", something Dean, in a rare moment of shrewdness, refers to as "the diary of a crazy person". He briefly bears a grudge against Rusty Venture for breaking the heart of his stepdaughter, Dr. Quymn, whom he has retained some affection for. Col. Gentleman lives in Tangier, it formerly being a haven for the world's elite and greatest intellectuals, but in recent years he has realized that he is the only one left, and is dejected that Kiki has broken up with him for the last time. At the end of season 5, he realizes that there is no reason for him to stay in Tangier anymore and moves back to the United States, becoming the Action Man's new roommate.

Kano (voiced by Christopher McCulloch): Retired member of the original Team Venture. He is a master of the martial arts and an accomplished pilot, and was likely inspired by the Green Hornet's assistant Kato. In earlier episodes, he never speaks and only communicates by way of origami and sparse gestures; however this is attributed to a vow of silence he'd taken as revealed in the episode "ORB". The vow was made when he took a great man from the world, which Brock believes was Jonas Venture Sr., when Brock asks him if he killed Dr. Venture Kano didn't answer. However, due to the fact Kano was depicted as already silent in flashbacks to the time Venture Sr. was alive as well as the introduction of the Blue Morpho, this theory seems questionable. As Col. Gentleman describes him, his hands are "powerful enough to crush a boulder, yet delicate enough to crush a butterfly." Although not a villain, his silent demeanor, fighting skills and brute strength all correspond with the bodyguard/henchman archetype found in many works of fiction, with particular similarities to Oddjob. Although a hulking, powerful fighter, he is still no match for Brock Samson, at least in his old age. In addition to his skill in fighting and origami, Kano also appears to be a capable aircraft pilot ("despite his racial handicap," according to Col. Gentleman). Kano has also displayed an ability to breathe fire in the episode "Now Museum-Now You Don't". During the commentary it is revealed that this is where his name originates in that it is short for "Volcano". The episode "Faking Miracles" reveals that Kano was originally the bodyguard of the Blue Morpho, The Monarch's father. In "Arrears in Science," it is finally revealed that the great man whom Kano killed before taking his vow of silence was the Blue Morpho; Jonas resurrected the Blue Morpho as the cyborg Venturion after his death in a plane crash, but Venturion malfunctioned and attacked Rusty, forcing Kano to snap his neck. According to the other members of the original team, Kano never spoke again after this event.

Otto Aquarius (voiced by T. Ryder Smith): Retired member of the original Team Venture. An exiled son of Atlantis, he is half-human and half-Atlantean, which grants him a greatly extended life-span and the power to communicate telepathically with sea-creatures, who obey his commands. Most recently, he has converted to either The Church of Jesus Christ of Latter-day Saints (according to the special features section of the Season 1 DVD) or the Jehovah's Witnesses (according to Christopher McCulloch's blog), though his bizarre appearance often sabotages his attempts at evangelism. Due to his newfound faith, he is now a pacifist (which seems to confirm that he is a Jehovah's Witness), limiting his usefulness to the reformed Team Venture. In a deleted scene, he refuses to work alongside Kano, Col. Gentleman, and the Action Man, accusing them of being, "an idolater, a sodomite, and a murderer" respectively; he goes on to explain that the only reason he went in the first place was to accumulate missionary hours (another nod to the Jehovah's Witnesses). He is a parody of aquatic characters such as Sub-Mariner, Aquaman and Abe Sapien of Hellboy fame.

Dr. Entmann (voiced by Stephen DeStefano): A tiny man that was left abandoned in a nuclear fallout shelter by Jonas Venture, Sr. In his previous heroic incarnation he was 15 feet tall, flabby, and curly haired–not unlike pro wrestler André the Giant–and went by the name Humongeloid, and according to Entmann, another accident caused him to become gigantic. Brock Samson finds Dr. Entmann in a disused and abandoned lab below the Venture Compound, where he had been trapped for some 30 years, ever since an experiment to shrink him went disastrously wrong. Both Dr. Entmann's name and character appear to be based on the Marvel comics character Henry Pym, who started out able to shrink to nearly microscopic levels and regain his original size as Ant-Man before gaining the ability to grow up to 100 feet tall. Dr. Entmann moves in with Action Man, and is later killed when Action Man sits in his rocking chair and crushes him.

Swifty (voiced by Brendon Small): An African-American boxer, and former bodyguard to Dr. Jonas Venture. In flashbacks, Swifty is shown using a pair of jet-powered boots. He currently suffers from Dementia from years of boxing, and is employed as a janitor on Spider-Skull Island by Jonas Venture, Jr.

Hector (voiced by Brendon Small): A Hispanic boy and childhood friend of Rusty Venture. Seen in a flashback using an Aztec calendar to prevent an arrow from injuring Jonas Venture, Hector then joined the original Team Venture as Rusty's companion. However, as revealed in "Powerless in the Face of Death", in the present day Rusty has no recollection of Hector or their adventures together. Hector reveals that he has been living in a part of the Venture compound closed off by Rusty years prior, unaware that it had been closed, or that Jonas Venture had died, at which point Rusty unceremoniously evicts him. Hector appears to be the proxy of Hadji from Jonny Quest in the original Team Venture.

Ook Ook: A cave man-like member of the team. In the present day, Ook Ook's body is encased inside a block of ice, though the circumstances surrounding this event have not been revealed.

The Office of Secret Intelligence is a branch of the United States government that handles supervillain activity, both combatting groups of supervillains or assisting super scientists and superheroes with their Guild of Calamitous Intent-assigned archenemies. A pastiche of G.I. Joe, in the 1980s they even fought against S.P.H.I.N.X. (itself a pastiche of Cobra Command) in the Pyramid Wars, during which the original S.P.H.I.N.X. was defeated. The O.S.I. operates from a hovering base and seems to answer to a division known as the Misters who are the go-between with the Secret President.

General Timothy Treister (voiced by Toby Huss): Commander of the O.S.I., he's a tough, no-nonsense, highly energetic military man. He seems to be based on a combination of General "Thunderbolt" Ross and Teddy Roosevelt. Treister is first mentioned in season 1's "Mid-Life Chrysalis", but first appears in person in the season 3 finale "The Family That Slays Together, Stays Together (Part II)"; after Brock Samson goes on the run from the hit put on him by Molotov Cocktease (that he was led to believe was placed by the O.S.I.), Treister leads the effort to find and debrief Samson. He later shows up to help coordinate between the O.S.I., S.P.H.I.N.X., the Guild of Calamitous Intent, the Revenge Society, and the Peril Partnership during Zeus and Zero's rampage across the world's sidekicks. Finally, in "Operation P.R.O.M.", Treister reveals he is dying of testicular cancer, but has been fooled by Mister Doe and Mister Cardholder into thinking he has been turned into a Hulk after experimental gamma raychemotherapy. After finally meeting with Col. Gathers, revealing he has discovered Doe and Cardholder are Guild double agents, he entrusts O.S.I. back to Gathers and shoots himself off into space in order to have his cancer cured by "alien technology". Treister reappears in "All this and Gargantua-2", where his frozen body is taken aboard the titular ship and upon being awoken believes that Billy and JJ are aliens and goes on a rampage after misinterpreting them as being hostile. He and JJ sacrifice themselves to stop Gargantua-2's self-destruction from hurting anyone, during which it is revealed that, as a result of the massive amounts of solar radiation his body was subjected to while he was in space, Treister actually is a Hulk-like creature.

Mister Doe and Mister Cardholder (voiced by Doc Hammer and Christopher McCulloch, respectively): Two Mister-level agents of O.S.I. They first appear in the episode "The Lepidopterists" to assist Dr. Jonas Venture, Jr., in his fight against his newly assigned archenemy The Monarch, as they plan on capturing The Monarch for killing so many previous archenemies. They regularly appear as assistants to General Treister, and are even made to guard the Venture family during "Blood of the Father, Heart of Steel" before Sgt. Hatred is assigned to them. In "Operation P.R.O.M." they reveal to Col. Gathers that they are Guild moles sent to trick Treister into thinking he has been turned into a Hulk, to prove to the President that Treister should be removed from his position and they should take his place. Their plan is foiled when Treister reveals to Gathers that he has discovered that they are moles, and that Mile High has been working for him as well.

Gen. Hunter Gathers (voiced by Christopher McCulloch): Brock's former mentor from when he was in training for the O.S.I. Gathers has since gone into hiding after undergoing sex reassignment surgery (SRS), taking a job as a dancer at Nightingales, a strip club. The character is modeled on Hunter S. Thompson, and his name is a play on the term hunter-gatherer. Other than Brock, Gathers was the only O.S.I. agent who believed the Guild was still in existence in the late eighties, as seen in "The Invisible Hand of Fate". Despite being extraordinarily eccentric, he seems to sincerely care about his job and defending his country. He also taught Brock the strict rule of never killing women or children, as that differentiated them from the "baddies". This is something he used to his advantage when he went rogue from the O.S.I. who then sent Brock to kill him (as Brock doesn't kill women). He is apparently a member of Molotov Cocktease's "Black Hearts" assassination guild, as shown in the scene following the end credits of "The Family That Slays Together, Stays Together (Part II)". However, despite the SRS, he still has the same face and voice as before—including perpetual five o'clock shadow. He also stated in "The Invisible Hand of Fate" that he wanted to be born with "big, beautiful tits", which turns out to be foreshadowing (down to the fact that he has large breasts, but can still grow facial stubble). The sex reassignment and apparent betrayal of the O.S.I. were revealed in the Season 4 opener to have been an elaborate ruse to infiltrate the Black Hearts; when Gathers and Samson were captured by Sphinx agents, Gathers revealed himself as an undercover Sphinx officer, complete with revealing the reversal of his surgery with the statement to Samson "You don't know DICK!", uttered while pointedly grabbing his own groin. In the episode Pinstripes & Poltergeists, it is revealed that Gathers and other members of the O.S.I., disgusted with its ineffectual bureaucracy, eventually quit the O.S.I. and took S.P.H.I.N.X's name and equipment to form an organization capable of covertly and effectively combating super-powered villains (mostly those who do not abide by the rules of organized villainy) against whom the O.S.I is powerless. S.P.H.I.N.X. seeks to terminate villains who do not abide by the rules of organized villainy mandated by institutions like the Guild of Calamitous Intent (basically acting as a regulator of sorts, keeping the more dangerous supervillains in check). Slogan: "If someone points a gun at you, call the police. If a bunch of guys are pointing guns at you, you call SWAT. If they're in spandex and pointing a super laser at you, you call the O.S.I.. And if they're dressed regular and they're pointing a super laser at your daughter, you call S.P.H.I.N.X." Hunter surrenders command of S.P.H.I.N.X. to 21 after he is promoted to O.S.I.'s General (and also taking the entire staff leaving 21 as the only remaining member of S.P.H.I.N.X.).

Shore Leave/Holy Diver: (voiced by Doc Hammer) A former O.S.I. agent fired for violating O.S.I.'s don't ask, don't tell policy. His appearance and code name seem to be a parody of G.I. Joe characters, as Shore Leave resembles the character Shipwreck. His other code name is taken from the Dio song Holy Diver. Shore Leave had joined Hunter Gathers in S.P.H.I.N.X.. In the episode Pinstripes & Poltergeists, it is revealed he and Mile High faked being a couple (while Mile High was only pretending to be in a gay relationship with Shore Leave, Shore Leave himself thought their relationship was real) as well as their conversion to religious fanaticism, for their cover. (Shore Leave's name is spelled "Shoreleave" in the Season 4 credits.) Shore Leave is often teamed up with Brock. He is also an extremely skilled combatant, matched only by Brock Samson though in contrast to Brock he favors firearms over melee combat (specifically a matched set of pistols, with which he is deadly accurate). He has started flirting with the Alchemist in the last episode of the 4th season, and ended up making out with him. It is also revealed in the Season 4 episode "Everybody Comes To Hank's" that he and the Alchemist were briefly in a sexual relationship, but Shore Leave broke it off and wiped the Alchemist's memory when he became too "possessive" and dumped his boyfriend to move in with Shore Leave.

Mile High/Sky Pilot: (voiced by Christopher McCulloch) A former O.S.I. agent fired for violating O.S.I.'s don't ask, don't tell policy. His appearance and code name seem to be a parody of a G.I. Joe character. He had joined Hunter Gathers in Sphinx. In the episode Pinstripes & Poltergeists, it is revealed he and Shore Leave faked being a couple (while Mile High was only pretending to be in a gay relationship with Shore Leave, Shore Leave himself thought their relationship was real) as well as their conversion to religious fanaticism, for their cover. His name is a reference to the mile high club, as well as to the 1968 song "Sky Pilot" by Eric Burdon & The Animals. In the season finale "Operation: P.R.O.M." it is revealed he was a double-agent working for the O.S.I..

Dr. Vulcano (voiced by Brendon Small): Dr. Vulcano is the surgeon who performs sex reassignment surgery on Hunter Gathers in the episode "Assassinanny 911". He later is seen assisting the Nazis in their creation of the dog containing Hitler's soul and removing H.E.L.P.eR's head from Brock's chest in the episode "Blood of the Father, Heart of Steel", where he is also revealed to be a member of S.P.H.I.N.X. under Hunter Gathers' command. In "O.S.I. Love You", Dr. Vulcano is seen to have been recruited into O.S.I. where he is in Dr. Venture's former O.S.I. lab on the hovering headquarters which has been turned into a laboratory housing two precogs who predict the future on a series of black spheres they excrete.

Headshot (voiced by Bill Hader): Headshot is O.S.I.'s top marksman, who worked on the mission to capture Monstroso and Molotov Cocktease. He and Amber are in a relationship. In a moment of infidelity, he attempts to examine who he believes to be the captive Molotov Cocktease only to discover Amber in her place. Although more shocking to him is the truth about Amber's hair color. Headshot may possibly be a reference to "Face" from "The A-Team" as well as a GI Joe character ("I only do two things, and I do them very well: I'm handsome, and shoot people.")

Amber Gold (voiced by Paget Brewster): Amber is a female operative of O.S.I.. She is left to examine Molotov Cocktease in captivity, and when believing that the Nozzle has detected a foreign object in her eyepatch, takes her eyes off Molotov, allowing Molotov to escape her constraints and disguise herself as Amber, using Amber's wig of platinum blonde hair that she uses to cover her own shorter natural blonde hair. She is in a relationship with Headshot, although it becomes strained when he discovers her blonde hair is a wig and feels she is hiding other things from him. She is also having an affair with Brock Samson.

Afterburner (voiced by Doc Hammer): Afterburner is a ninja operative of O.S.I. who wears a complete bodysuit akin to Snake Eyes of G.I. Joe.Just like Snake Eyes, he wears the suit to hide his horribly disfiguring burn scars.

Shuttle Cock: An O.S.I. operative themed after an astronaut who wields a badminton racket as a weapon. He is a double-agent killed by Molotov Cocktease.

Slap Chop: An O.S.I. martial artist operative resembling Iron Fist and Vince Offer, known for pitching the "Slap Chop" kitchen utensil on infomercials. He is a double-agent killed by Molotov Cocktease.

Bum Rush: An O.S.I. operative themed after a homelessbeggar who keeps his weapons in a shopping cart. He is a double-agent killed by Molotov Cocktease.

Tank Top: An O.S.I. operative who wears an armored tank top that has a tank cannon on it. He is double-agent killed by Molotov Cocktease.

Snoopy (voiced by John Hodgman): A meek O.S.I. operative who works on the bridge and assists General Gathers.

The Guild of Calamitous Intent is the primary organization of antagonists in the series. It acts as a sort of supervillain trade union, providing benefits such as health insurance and setting the rules of conduct between its members and their enemies; the Guild acts as a stabilizing influence on the world of super-villainy, as without it they would be unchecked free agents with no rules restricting their behavior. As Brock Samson put it: "These guys like their system, it's what they do; you take that away, and you're looking at a bunch of pissed off nut-bags with ray guns." The Guild not only serves to organize those mentally unstable individuals prone to acts of villainy into an efficient force, but at the same time it also acts as a brake on their more murderous impulses, as well as restricting attacks to Guild-approved targets. It is led by a mysterious figure known only as "The Sovereign" (thought to be David Bowie, but later revealed to be a nameless shapeshifter), and a group of villains called the Council of Thirteen. The current incarnation of the Guild (or at least its leadership) is implied to be a haven for missing and/or presumed deceased rock stars. In "All This and Gargantua-2", most of the Council of 13 is killed by the Sovereign as part of a gambit to draw out the Investors. The only survivors being Dr. Mrs. The Monarch, Dr. Phineas Phage, Dr. Z, Red Mantle, and Dragoon. Dr. Henry Killinger forges a new Council of 13 from the remaining councilmen and surviving Revenge Society members (sans Richard) after his slaying of the Investors in order to restore the balance between the OSI and the Guild, but declined the role of Sovereign, claiming his work was done. Season six introduces the New York branch of the Guild, which is made up of the most dangerous supervillains the organization has to offer. It is later revealed that the original Guild charter does not mandate that the Council must have exactly thirteen members, and members of the Council cannot be actively arching their enemies.

The current incarnation of the Guild was apparently founded around 1959 by Phantom Limb's grandfather, but its history can be traced back to the late Victorian era, where it was a heroic organization led by Colonel Lloyd Venture, Rusty Venture's grandfather, dedicated to the protection of an item known as the "ORB", an enigmatic sphere that had been built over the centuries by humanity's greatest individuals. The Guild then split over how to use the ORB, with Fantomas founding the Guild of Calamitous Intent (who wanted to use the ORB to control mankind) in 1910 while Lloyd founded the modern version of the OSI (who wanted to use the ORB to help mankind).

The Monarch (voiced by Christopher McCulloch): Dr. Venture's self-styled nemesis. His real name is Malcom Fitzcarraldo. He is obsessed with monarch butterflies, which he claims raised him as a child after he survived the plane wreck which killed his parents in the New JerseyPine Barrens. In fact, he only spent a few months unsuccessfully imitating them before returning to claim his inheritance, and still seems to have almost no understanding of their biology or behavior. He then attended State University where he began "arching" Dr. Venture, but for reasons as yet unrevealed. He then began working for a variety of villains, and was employed by Phantom Limb as Shadowman 9, until he became The Monarch and seduced Dr. Girlfriend (then known as Queen Etheria). Though he frequently describes himself as Dr. Venture's nemesis, their rivalry resides almost completely in The Monarch's imagination. In reality, Dr. Venture considers him more a nuisance than a genuine threat, and is even fine with leaving his sons in The Monarch's care due to his general incompetence. He is also the unofficial arch-enemy of Captain Sunshine, to whom he is far more ruthless, even brutally killing Wonder Boy III and sending the hero his charred corpse. The Monarch eventually lost his privilege to Arch Rusty after it was discovered that he was not a Guild-sanctioned villain, and upon registering killed five heroes and super-scientists he had been assigned to before being given the job of Arching Jonas Jr. until The Monarch uses the Guild clause of "prior escalation" to be able to attack Rusty again. His plans against the Venture family are usually bizarre and fail for a number of sad reasons. For instance, his first attempt on Venture's life instead mutilated his lab partner, Werner Ünderbheit (Ünderbeit believes Venture was responsible). At the end of season one, he was convicted of murder and sentenced to prison after being framed by the Phantom Limb. In the second season, he escapes and begins to rebuild his criminal operation, reuniting with Dr. Girlfriend in the process and eventually marrying her. As of the third season, the two have moved into Phantom Limb's old mansion in a gated community called Malice. In the fifth season of Venture Brothers, there is a photo The Monarch finds while undercover at the Venture compound of him as a toddler playing with Rusty and accompanied by his parents and the Venture family, suggesting The Monarch and Rusty could have been childhood friends. In the end of season 5, with the Cocoon and his Malice estate destroyed, The Monarch, his wife, and Henchman 21 move into The Monarch's childhood home in hopes of finding answers, unaware that the Revenge Society had been squatting there. He also loses his rights to fight Dr. Venture, as the loss of his cocoon and henchmen have lowered his Guild ranking substantially. In the episode "Faking Miracles" The Monarch discovered that his father was actually the Blue Morpho, a vigilante superhero who was good friends with Jonas Venture. The Monarch then took up his father's hero identity and, along with Henchman 21, began killing New York Guild members who were antagonizing Dr. Venture so that he could move up the waiting list. In Season 7, it is implied that The Monarch's mother slept with Jonas Venture to conceive him, potentially making him the half-brother of Dr. Venture; the further reveal that The Monarch and Dr. Venture are blood relatives makes the likelihood very high, though it doesn't rule out cloning or another familial relationship.

Henchman 21/Gary Fisher[3], briefly S.P.H.I.N.X. Commander and occasionally the Viceroy (voiced by Doc Hammer): A pop-culture geek who at the beginning of the series is a henchman for The Monarch, always seen with Henchman 24. He writes (or at least provides the cover-photo for) "Flight of The Monarch", a tell-all that starts the chain of events ending in The Monarch's incarceration. In the first episode of season two, being without costume for the first time, he is described by 24 as resembling Kevin Smith, although Doc Hammer himself stated the "Gary" portion of the character is in fact inspired by Ken Plume on Ken's "A Bit Of A Chat" podcast. He briefly toys with the idea of becoming a supervillain himself, "the Viceroy". He claims that he joined the world of henching when he was kidnapped by The Monarch's henchmen when he was 15. When not henching, Number 21 runs a comic book hotline, the "Atomic Comic Collection Connection" from his bedroom. It is also revealed that he has a crush on Doctor Girlfriend. After the death of Henchman 24, he goes into heavy combat training and emerges with sufficient strength and martial prowess (not to mention the new nickname "2-ton 21") to contend with former-tormentor Brock Samson. He and Samson then work together to defeat Monstroso, a common enemy. Henchman 21 still speaks to what he believes is Henchman 24's ghost, though Henchman 24's ghost suggests that he is only a figment of Henchman 21's imagination (simultaneously confirmed and refuted in Operation: P.R.O.M.), in echos of Rudyard Kipling's classic story "The Man Who Would Be King". In "Operation P.R.O.M.", 21 was offered a chance to work with the anti-unlicensed superhero team, S.P.H.I.N.X.. He found he enjoyed working "with guys who actually know what they're doing" for once, and began to question his dedication to the ways of The Monarch and evil in general. By the end of the episode, he realizes that being a villain is not for him, and quits the ranks of The Monarch. In "From the Ladle to the Grave: The Story of Shallow Gravy" 2011 Venture Brothers special which takes place after "Operation P.R.O.M," he is interviewed while wearing a S.P.H.I.N.X. uniform with his face censored, and using the Viceroy name. After "Operation P.R.O.M." Gary becomes the commander (and only remaining member) of S.P.H.I.N.X., which does not last long when the former members of the original S.P.H.I.N.X. take over, forcing the O.S.I. to shut S.P.H.I.N.X. down for good. Gary lives in the backyard of the Venture Compound, as S.P.H.I.N.X.'s headquarters is destroyed by Dr. Venture and Sgt. Hatred when they believe Gary has planted bombs under the Venture Compound, as he can identify them as his own painted the colors of The Monarch, when they were in fact planted by The Monarch and Dr. Mrs. The Monarch in their earlier infiltration attempt. He later helps Hank and Dermott to try to get to Teddy by adopting his "Viceroy" moniker in a bank robbery to get into the Dunwitch Asylum for the Criminally Insane. After attempting to help Hatred retrieve Dr. Venture, he leads The Monarch henchmen in overthrowing Tim Tom and Kevin and decides to rejoin the ranks of The Monarch, returning not out of loyalty to The Monarch or the henchman lifestyle, but because The Monarch is the only friend he has left. By Season 7, 21 finds himself the only remaining henchman of The Monarch. He then assists The Monarch in the killing of Dr. Venture’s archenemies, though he finds himself burdened by more and more guilt for doing so, as he has never intentionally killed someone before. He attempts to end the killing by kidnapping several of the archenemies he would have had to go after and merely holding them captive until The Monarch was made Dr. Venture’s official antagonist again, but one of them turns out to be a cannibal and kills the others.

Henchman 24, (voiced by Christopher McCulloch): a tall, thin man with voice characteristics resembling comic Ray Romano and was described by 21 in the first episode of the second season as resembling Jerry Seinfeld with a unibrow. He and Henchman 21 frequently have arguments about unusual hypothetical situations. He tends to repeat words that are dirty or have a double entendre like "loin" and "jerkin". Number 24 served as Shadowman 24 for Phantom Limb at the same time The Monarch was Shadowman 9. The Monarch promised to make him his "number 2" in return for a favor, a promise which has never been carried out (possibly due to Dr. Girlfriend's reservations about 24, who was wearing The Monarch's Shadowman 9 uniform as part of the aforementioned arrangement with The Monarch, due to issues with 'staring'). Number 24's powder blue Nissan Stanza becomes the replacement Monarch Mobile after The Monarch's lair is destroyed but is promptly stolen by a fleeing prostitute. The Stanza later inexplicably reappears in the garage of The Monarch's Cocoon. It was heavily damaged when the Cocoon crashed in the Grand Canyon. The Monarch doesn't remember much about 24 besides the fact he thinks his voice sounds like aforementioned Ray Romano. A former factory worker before he joined up with The Monarch, 24 has revealed to Dean that his ex-girlfriend married his father and that he has always wanted to be a cabinet maker. Number 24 dies in an explosion at the end of the season three finale. However, a deleted scene reveals that 24 had faked his death so as to leave the henchman lifestyle behind and is now working at the gas station his father owns[citation needed]. His supposed skull makes appearances throughout season 4 as an object with whom #21 converses, like they did previously. In Pinstripes & Poltergeists, #24 is apparently a ghost that has decided to haunt #21 due to lack of options, the other choices being the Cocoon lair, which gets blown up frequently, or his ex-girlfriend from when he was 15, which would have been 'way too creepy' as she no longer likes him 'in that way'. In Operation: P.R.O.M., it is revealed that 24 was not actually a ghost throughout Season 4, but a figment of 21's grief-stricken imagination. 21's acceptance of this allows him to finally accept 24's "death". Although he still harbors a suspicion that someone is responsible for 24's death, and decides that Tim Tom and Kevin are the ones responsible, and blaming them allows The Monarch's henchmen to overthrow them.

Dr. Mrs. The Monarch, néeDr. Girlfriend (voiced by Doc Hammer): Wife and assistant to The Monarch. Her real name is Sheila, although her last name is still unrevealed. She bears a remarkable similarity to Jacqueline Kennedy Onassis, and even more so to Josie Schuller from Joëlle Jones comic book series Lady Killer. For the most of her career as number 2 to The Monarch wore the former First Lady's famous short pink jacket and pillbox hat, and shares her Long Island accent (Surprisingly and humorously, as was evidenced in the episode "Home Is Where the Hate Is," she is shown to be completely unaware of who Jackie Onassis was). Her comically deep voice (the character is voiced by a man) is a result of her previously having had a severe smoking addiction, and is a parody of Jacqueline Kennedy Onassis' relatively low voice for a woman, and at one point, the creators claimed that they originally imagined her as sounding like actor Harvey Fierstein. Rumors that she is transsexual have been dispelled as a red herring. She was introduced to the world of costumed villainy by Phantom Limb, her then-lover and former professor. She initially failed as an independent villain named Lady Au Pair, assisted by her Murderous Moppets Tim Tom and Kevin, who constantly violated Guild bylaws by murdering her assigned heroes. She then served as Phantom Limb's second-in-command under the name Queen Etheria, until she was seduced by The Monarch at a party. Dr. Girlfriend was the undisputed brains behind The Monarch's operations, but she felt unappreciated by him. After a short separation, Dr. Girlfriend and The Monarch renewed their relationship on the condition that The Monarch stop arching Dr. Venture and make Dr. Girlfriend his partner, not just his number 2. They were married in the Season 2 finale and recognized by the Guild of Calamitous Intent as "villain and villainess" in Season 3. She is apparently close friends with David Bowie whom she greeted affectionately when he arrived at her wedding. David Bowie also walked her down the aisle at her wedding serving as bridal escort. Dr. Girlfriend now goes by the name Dr. Mrs. The Monarch and has designed a new butterfly-themed costume for herself. According to the show's creators, her title of doctor is honorary in nature. Her doctorate was received after donating a large sum of money to an unnamed evil college. After the death of Vendata, the Sovereign approaches her to be the new Councilman 1 of the Council of Thirteen, but she has yet to accept or decline the offer, requesting that she go over it with The Monarch first. However, The Monarch feels she will likely take the offer. In the end, she does and barely survives the Sovereign's attack on the Council, becoming a part of the new Council of 13.

Tim-Tom and Kevin (voiced by Christopher McCulloch and Doc Hammer, respectively): Achondroplastic dwarves who were Dr. Girlfriend's Murderous Moppets in her solo career as Lady Au Pair. They apparently remain on good terms with her, helping in her application to be the Order of the Triad's nemesis, helping her at her wedding, and organizing the rebuilding of the cocoon after its destruction. They speak to Dr. Girlfriend in a respectful manner, but outside of her presence, they are both surly, foul-mouthed, and utterly psychotic (they seem to ferociously attack with their matching stilettos with very little provocation). Both of them wear Little Lord Fauntleroy suits and ribboned hats. Tim-Tom is white (and speaks with a cockney accent) and wears a blond curly-top wig, whereas Kevin is black, and does not have a wig (he appears to have a jeri-curl, and thus curly hair like his partner). However they are now seen wearing matching larva uniforms now being associated with The Monarch. They apparently also deceive their mistress: she tells The Monarch that they were upset that henchmen pick on them, and that #24 was bullying them—when in fact they terrorize (and routinely brutalize) the henchmen and Tim-Tom savagely knifed (and nearly murdered) #24 after he jubilantly poured Gatorade on him as a mischievous affirmation of the Moppets' leadership. Dr. Girlfriend seems to completely believe the Moppets' story, but The Monarch seems dubious. After Dr. Girlfriend becomes Dr. Mrs. The Monarch, the Moppets apparently officially join The Monarch's organization, performing reconnaissance on the Venture compound for The Monarch (disguised as child participants in Dr. Venture's "Day Camp for Boy Adventurers") and accompanying the villainous couple on a mission while costumed as "the Pupaetwins". Dr. Girlfriend treats them both as though they were her children, and they call her "ma'am" in turn but both of them also have sexual fantasies about her. Tim Tom admitted to Kevin that he sneaked a look at her panties once when she knelt in front of them, and both of them enjoyed receiving hugs from her when she donned her revealing Dr. Mrs. The Monarch costume, taking the opportunity to openly stare at her breasts. While the Moppets have been shown to be relatively surly and fearless, they both were intimidated by The Monarch in "Return to Malice" when he peevishly confronted them outside of his wife's presence. It is implied in "Bright Lights, Dean City" that they may actually be sleeper agents working for Phantom Limb—a theory supported by the fact that Phantom Limb is fully aware of Henchman 21's mental problems. During season 5, with the absence of 21 in the Cocoon, they slowly begin to take over, with the remaining members of the Fluttering Horde afraid of them. Upon his return, 21 blames the two for the death of 24, and the other henchmen follow his lead, ending the Pupaetwins' rule as well as their lives, which The Monarch was not oblivious to.

Watch and Ward (voiced by Christopher McCulloch and Doc Hammer, respectively): Watch and Ward are the communications liaisons for the Guild of Calamitous Intent, speaking with prospective protagonists and antagonists respectively to adequately provide proper arching assistance. Watch wears a tactical eyepatch over his left eye and appears to be bald, while Ward wears one over his right and has hair sticking out from beneath his cowl. The two frequently get into arguments based on actual conversations between McCulloch and Hammer, such as Ward being upset that Watch drank his juice box. Both are unaware that the Sovereign is not David Bowie and have multiple records signed by him. In "All this and Gargantua-2, they are revealed to be the "Guild Resistance" and save Dr. Mrs. The Monarch and Phineas Phage from the Sovereign.

Dr. Henry Killinger (voiced by Christopher McCulloch): A supervillain parody of diplomat Henry Kissinger and magical nanny Mary Poppins; he is never without his "magic murder bag". Killinger is a highly skilled businessman and negotiator and demonstrates a keen understanding of legal matters, particularly tax law. He is shown to have magical abilities, although the nature and extent of his powers are unclear. Some characters have a great deal of trouble understanding him when he speaks. Killinger's major appearances have twice involved spontaneously offering his services as strategist, business consultant, and/or motivational coach to main characters, free of charge, in the episodes "I Know Why The Caged Bird Kills" and "The Doctor Is Sin". In both cases, his influence results in a substantial increase in the efficiency with which his clients conduct their affairs. He seems to be a 'villainous' counterpart to The Master of Doctor Orpheus, both in his role as a mentor and life-coach to super-villains, and due to the fact that he possesses greater magical power than Doctor Orpheus (Doctor Orpheus' magic is completely ineffective against Dr. Killinger, as seen in 'The Doctor is Sin'). He also appears conducting the marriage services during The Monarch's wedding to Dr. Girlfriend in the episodes "Showdown at Cremation Creek (Part I)" and "Showdown at Cremation Creek (Part II)". Although, as a supervillain Killinger is capable of dispassionately murdering adversaries, he is also shown to be capable of quickly forming warm friendships, as well as acts of great kindness. He develops an avuncular relationship with the Venture boys in "The Doctor Is Sin", to the extent that the two of them refer to him as "Uncle Henry". In "I Know Why The Caged Bird Kills", he goes to great lengths to reunite Dr. Venture and Myra Brandish, although he fails, succeeds in reuniting The Monarch and Dr. Girlfriend. In the DVD commentary for "I Know Why the Caged Bird Kills", it is mentioned that Killinger may actually be the alter-ego of Henry Kissinger in the Venture universe. Killinger later joins the Revenge Society as run by Phantom Limb, for as-yet unknown reasons. It is revealed in "All this and Gargantua-2" that he is Apeliotes, one of the Investors. Killinger then kills the Investors for meddling in the affairs of mortals. He then forms the New Council of 13.

The Sovereign (voiced by Christopher McCulloch, David Bowie impersonated by James Urbaniak): The mysterious entity who runs the Guild of Calamitous Intent. He communicates principally by use of tele-screens which distort his face and voice. It was long believed that the Sovereign's true identity is that of David Bowie, but it is revealed in "O.S.I Love You" that the true Bowie is merely an acquaintance of the real Sovereign, who is an unknown shapeshifter that often uses Bowie's appearance as a disguise (as he "wants to be anyone but himself"), a reference to the real Bowie's reputation for adopting new musical styles and possibly the ability of his character in the movie Labyrinth. According to Monstroso, the true form of the Sovereign is that of one of the creatures on the cover of Diamond Dogs. He has also taken on the guises of other human beings as well as animals and inanimate objects, and has been seen to possess other supernatural powers, such as immunity to Phantom Limb's death touch. In "All this and Gargantua-2", he murders most of the Council of 13, and masterminds an attack on Gargantua-2 as part of a grand scheme to finally kill the Investors, and is apparently accidentally killed by Headshot while in the form of an eagle. The previous Sovereign was known as Force Majeure, also the name of a Tangerine Dream album. It is revealed in season 7 that he was responsible for starting the Pyramid Wars of 1987 between S.P.H.I.N.X. and O.S.I., when he impersonated S.P.H.I.N.X. Commander and blamed the organization for the "Movie Night" massacre on Gargantua-1.

Iggy Pop (impersonated by Christopher McCulloch): American rock musician and one of the Sovereign's henchmen. Iggy Pop has the ability to create spheres of energy that explode when he issues the command "Pop". He betrays the Sovereign in favor of Phantom Limb, but the Sovereign later kills him for his betrayal.

Klaus Nomi (impersonated by Christopher McCulloch): German singer and one of the Sovereign's henchmen. Klaus Nomi has the ability to sing in a hypersonic voice and his bowtie can fly off as a projectile. He betrays the Sovereign in favor of Phantom Limb, but the Sovereign later kills him for his betrayal.

Monstroso (voiced by Christopher McCulloch) is considered the most evil of evil men as he is both a lawyer with the Mammoth Corporation and a supervillain licensed with the Guild of Calamitous Intent. His size is enormous, with a lap sufficient for Dr. Girlfriend and a brace of four additional revelers as can be seen in a picture in the book The Flight of The Monarch. Monstroso is prosperous enough to have employed the bulk of The Monarch's men while he was in prison, no doubt due to his lawyer and super villain vocations. His voice is deep and gravelly, resembling the stereotypical demonic voice. His lawyer attire consists of a standard business suit with pinstripes and a red shirt. When he conducts Guild business, however, he dons a red hood with horns, in accordance with Guild code. His coworkers at his law firm don red cowls with black M's on the top when they are portraying his henchmen and do not change out of their own business suits. Among his other diplomas, he has one from the Rancor University of Global Management, alluding to the possibility that he has aspirations for world domination. He wears a ring on his left ring finger suggesting he is married. In "O.S.I Love You," it is revealed that his ring contains a hidden camera, allowing him to collect information on people he plans to double-cross. He smokes cigars and constantly offers them to his guests. He also has a penchant for the double-cross, a fact Dr. Girlfriend reminded The Monarch of when he tried to make a deal with him. He was said to have been at attendance at The Monarch and Dr. Girlfriend's wedding, but he was not seen on screen. Brock believed Dean may have been torturing him with Snapple facts, when Dean was, in fact, hallucinating in the bellows of the Cocoon. In "Pinstripes & Poltergeists", he tries to double cross The Monarch by seizing his arch-enemy's property and his own through legal means. He was prevented by Henchman 21 and Brock Samson. In "The Silent Partners", Monstroso has the Investors kidnap Billy Quizboy, we learn that he is dying of heart failure and requires a transplant, namely the heart taken from King Gorilla by an agreement he made with the Investors to rescind his life sentence. Billy was chosen because of his skills, and the Investors would return the favor by forging documents signed by Billy to "officially" give him credentials to be legally recognized as a doctor and "immortality" for his recognized fame as a great surgeon because the surgery is so difficult. (and performed in international waters). Billy completes the transplant, and the Post credits scene, Monstroso appears to be recovering from his surgery, although he appears to be unaware that he is no longer on his boat but actually at the Sphinx headquarters on the Venture compound, Billy checks on him and returns to Brock. The only thing Brock is worried about is if Monstroso is “well enough so I can kill him yet?”. However, in "Operation: P.R.O.M.", Monstroso is rescued by Molotov, and it is revealed that he and Molotov are in a romantic relationship. After the limousine he is being rescued by Molotov in falls off a cliff, Brock finds it in the season 5 premiere, and finds Monstroso's "body" was a fake, and with no trace of Molotov. He and Molotov are eventually captured by O.S.I. in "O.S.I. Love You", but he is killed by the Investors after he reveals too many guild secrets to Brock. His true fate is kept unknown to Brock, as Brock never sees the Investors.

Torrid (voiced by Christopher McCulloch) is the arch of the Order of the Triad. He is first assigned as their arch enemy in the episode Fallen Arches when he kidnaps Triana Orpheus to the Torrid Zone ("Fallen Arches"). He has fire-based powers. He later steals the All Seeing Orb, during which time The Alchemist and Jefferson Twilight start to doubt the utility of having an archenemy ("Showdown at Cremation Creek"). Torrid's final appearance is when he attempts to open a portal to the Second World, unwittingly being sucked into it and then summoning an elder god that the Triad are unable to defeat, leaving Orpheus' protege the Outrider to save them all. Torrid is saved by the Outrider, only for Torrid to attack him with an incantation, disappearing once the spell is complete ("The Better Man"). By "Operation: P.R.O.M." when the Alchemist contacts Watch and Ward for information as to what the "Rusty Venture" sexual act consists of, they first rebuff him for contacting them about the death of Torrid.

Truckules (voiced by Christopher McCulloch): A truck- and Hercules-themed supervillain, and former Number One for Dr. Mrs. The Monarch, from whom she learned how to hotwire any vehicle. His upperbody resembles Optimus Prime's, and is so wide that when he attends The Monarch's wedding he requests two seats.

The Intangible Fancy (voiced by Christopher McCulloch): A supervillain who is intangible. He attends Dr. Venture's yard sale to buy something, but is caught in the fight that ensues. He is later questioned by the Council of 13 after attempting to smuggle contraband.

The Investors (Caecius: voiced by Doc Hammer; Skiron: voiced by John Hodgman; Lips: voiced by T. Ryder Smith): A mysterious group of supervillains who first appear in "Pinstripes & Poltergeists" as members of the Guild aligned with Monstroso. Their names correlate to three of the four lesser wind deities of the Anemoi They have the ability to appear out of thin air and phase through solid matter. They invest in Conjectural Technologies, allowing Billy and Pete to live comfortably, until Billy sees them appear out of thin air to harvest King Gorilla's heart. They later kidnap Billy so he may perform a heart transplant on Monstroso, with the pay being a proper Doctor of Medicine degree. They are on the top of both O.S.I. and the reformed S.P.H.I.N.X.'s list of targets, but they cannot be captured. They later appear in "O.S.I. Love You" disguised as O.S.I. Mister level operatives Mister Frost (voiced by Christopher McCulloch), Mister Sample (voiced by Dana Snyder), and Mister Yourname (voiced by Brendon Small), the last of which has not been properly inducted to interrogate those on board about what has happened to Monstroso and Molotov Cocktease. They kill Monstroso during Brock's interrogation earlier in the day. The ruse works until the actual Mister operatives come to interrogate, whereupon Gathers discovers the Investors have already left with all of the documentation of their own debriefing. They are present for the opening of Gargantua-2, with the Sovereign planning for a massive plan to attack the station with the ultimate goal of killing the Investors. They escape, and then confront their brother, Dr. Henry Killinger, who ultimately kills the Investors in a mental duel.

Augustus St. Cloud (voiced by Christopher McCulloch, originally James Urbaniak) is the inordinately wealthy former rival of Billy's from their quiz show days, both having been collectors of sci-fi and Rusty Venture memorabilia. He first appears at Dr. Venture's tag sale, receiving the brunt of Baron Ünderbheit's attacks due to The Monarch's interference. He later appears amongst supervillains, despite not yet being an official member of the Guild. After giving a sizable donation to the Guild's Widows and Orphans charity, he is inducted into the Guild and allowed to pick from a group of archnemeses, but demands he get Billy Quizboy, with Watch and Ward acquiescing to his demands after another sizable donation. The arching of Billy comes to a head when Billy and Pete White must attempt to retrieve several items St. Cloud bought off of Dr. Venture to fund the Palaemon Project, discovering St. Cloud's Asian albino henchman "Pi Wai" (more collectible than a normal albino). After refusing to eat $1 worth of pennies, the exact value that Billy had beat St. Cloud in an eBay auction years earlier, Billy bests St. Cloud in a trivia contest once more, winning back Venture's hovercraft, needed to deal with the Palaemon Project mutants, and H.E.L.P.er, who had also been sold to St. Cloud. St. Cloud's signature features are his short and stout stature, deadpan voice, round dark glasses, and collection of ginger paige-boy style wigs. Because of his incredible wealth and somewhat bratty personality, St. Cloud tends to use money in order to persuade people or purchase anything that would help him get his way.

The Council of Thirteen: The governing body of the Guild of Calamitous Intent. Known members are:

Councilman 1: Vendata (voiced by Doc Hammer): A cyborg formerly known as Venturion created by Dr. Jonas Venture, Sr. who at one time, tried to strangle young Rusty. Now a supervillain, Dr. Venture still sees him in his nightmares. O.S.I. tries a sting operation where they have Ghost Robot act as Galacticon to try to get information on the Council of Thirteen out of Vendata, but he is accidentally killed by Brock Samson. In his final moments, Vendata recalls crashing in an airplane and needing to know where his wife is, suggesting he may be the father of The Monarch having been rebuilt as a cyborg following the plane crash that orphaned The Monarch years ago. His position is replaced by Dr. Mrs. The Monarch. It is later revealed, when Brock attacked him that he survived and regained his memories, it turns out he is indeed The Monarch's father who was also the Blue Morpho before the crash. He was found by Dr. Z in the Venture Compound's dumpster and reprogrammed to be a supervillain, resulting in him joining the Guild. Early in his career as a villain he was a member of a gang of young supervillains who tried to carry out an unauthorized arch of Jonas aboard Gargantua-1. Vendata opened the station's bay doors after a confrontation with Jonas, resulting in the Movie Night massacre. He finally is destroyed for good while fighting with Jonas's preserved robotic body near VenTech Tower, with his head taken by O.S.I. for studying. Just before his death, he reunites with his son and The Monarch realizes his identity.

Councilman 2: Wild Fop (voiced by Christopher McCulloch): A Restoration-themed supervillain who first appears in an informational video given to Dr. Orpheus after he is approved for a supervillain. Killed by his dogs (via a trick perfume) in "All this and Gargantua 2".

Councilman 3: Red Mantle (voiced by Doc Hammer): A magic-wielding supervillain, who currently has Dragoon attached to his neck. He is seen to have elemental powers. He alludes to the fact that he is actually Buddy Holly, having survived "The Day the Music Died" with the Big Bopper (Dragoon). The character's voice favors that of 'Phineas J. Whoopee' (voiced by actor Larry Storch) from the old Tennessee Tuxedo cartoon series. The two are collectively dubbed "Red Dragoon" in season 6.

Councilman 4: Boggles, the Clue Clown: A clown-themed supervillain and former archenemy to Captain Sunshine. He is a pastiche of the Joker and the Riddler, with Dragoon saying that his jokes were tedious and his riddles obvious. He is found dead of a heart attack, possibly as a result of his identity being revealed to Brock by Monstroso, his position filled by Dr. Phineas Phage.

Dr. Phineas Phage (voiced by Bill Hader in season 4, James Adomian in seasons 5, 6 and 7): A bacteriophage-themed villain who has a cybernetic body capable of flight and a group of henchmen called the "Pro-Teens". He first appears in "Pomp & Circuitry", where he is the Guild-assigned archenemy to Richard Impossible. Happening upon Phantom Limb's confrontation with Professor Impossible, he is attacked by the escaped villain but manages to survive and alert the Guild. In "Any Which Way But Zeus", he has a cameo appearance alongside the other villains and heroes whose followers were kidnapped. Later, following the funeral of Boggles the Clue Clown in the season 5 episode "Bot Seeks Bot", Phage is appointed by the Sovereign to become the new Councilman #4. In order to earn this position, he memorized the entire book of Guild law to pass his exam, but later is still outwitted by Dr. Mrs. The Monarch in an argument on the subject. In "All this and Gargantua 2" he is the only other Council member to survive, escaping with Dr. Mrs. The Monarch but parting ways with her after getting out of Guild HQ. After the Guild reforms, they bring Phage back on as a Councilman. However, in "The Terminus Mandate," he is not seen among the current members of the Council. He is subsequently revealed to be in a coma in "The Saphrax Protocol" due to injuries he suffered when his cybernetic body caused the teleporter he was using to malfunction.

Councilman 6: Monseñor (voiced by Larry Murphy): A priest and lucha libre-themed supervillain. He delivers the eulogy at Boggles' funeral. Killed by poison gas by the Sovereign in "All This and Gargantua 2".

Councilman 7: Don Hell (voiced by Christopher McCulloch): A magic-wielding supervillain who owns a night club for other supervillains named Don Hell's. Upon discovering Dr. Venture and Billy Quizboy in his night club, he attempts to provide entertainment to his patrons by torturing them until Dr. Mrs. The Monarch reveals it is a violation of Guild bylaws to do such things to another member's archenemy without approval. He is loosely based on the real life New York City club promoter Don Hill. Killed by drinking acid in "All This and Gargantua 2".

Councilman 8: Dragoon (voiced by Christopher McCulloch): A dragoon-themed supervillain whose head has since been sewn onto the body of Red Mantle. He is highly critical of fellow supervillains, and believes that all magic is an abomination. Dragoon is slowly going senile, believing himself to be from the 16th century as well as mistaking real events for those from Wacky Races. It is suggested that he is the Big Bopper, having survived "The Day the Music Died" with Buddy Holly (Red Mantle).

Councilman 9: Steppenwolf (voiced by Christopher McCulloch): A werewolf-themed supervillain. He owns a car similar to that owned by the family in The Munsters. Killed by a car bomb in "All This and Gargantua 2".

Councilman 10: An unknown insect-themed armored supervillain who does not speak. He seems to resemble the protagonists of Japan's Kamen Rider Series, even possessing the characters' signature belt. While out at Don Hell's nightclub with fellow councilmen, he orders a kamikaze.Killed by a car bomb in "All This and Gargantua 2". The Art of the Venture Bros book mentions that the creators never settled on a name for this character but the name Omocha Bug may have been used in an early script.[4]

Councilman 11: Mommy Longlegs[5] (voiced by Paget Brewster): The only currently female member of the Council of Thirteen, she does not attend the congratulatory party for Phage as her grandchildren are coming to town for the weekend. Her silhouette resembles that of background character Mommy Longlegs, a spider-themed supervillainess, one among the many kidnapped by Zeus and Zero in "Any Which Way But Zeus". Killed by gunshots fired by a Guild murderbot while making her escape from the Sovereign's headquarters in "All This and Gargantua-2".

Councilman 12: The Nerve (voiced by Christopher McCulloch): A supervillain who is a sentient nervous system with no body, floating in a transparent humanoid suit. Found dead in a dumpster by Dermott in "All This and Gargantua 2".

Councilman 13: The Sovereign

Wide Wale (voiced by Hal Lublin): A leader of the New York branch of the Guild, he is brought in to help shore up support for the Guild and the Council after the events of Gargantua-2. He agrees to join only if he is given the arching rights to Dr. Venture. His real name is Chester Ong, and is the younger brother of Doctor Dugong, a super-scientist The Monarch seemingly killed. As a result of a laboratory accident, he has physical aspects of whales as part of his biology; these traits were inherited by his daughter Sirena. In Season 7, he forbids his daughter from seeing Hank Venture since he didn't approve of him. He later captures The Monarch (masquerading as Blue Morpho) and tells him that he plans to kill him out of revenge for his brother's death. He also tasks Hank with killing him but he refuses and just when Wide Wale is about to do it. Dr. Mrs. The Monarch and Red Death appear with Dr. Dugong who grew a new head, allowing him to survive The Monarch's attempt on his life before he went into hiding, provided by the OSI. Wide Wale is then faced with dealing with his daughter and brother who are angry that he didn't tell him about Dugong. In "The Terminus Mandate" he resigns from his seat on the Council, as he is unable to let go of his personal vendettas though remains an ally to them. The name "Wide Wale" is a fabric joke: wales are the ridges in corduroy, and the noise from his corduroy suit in his first appearance is loud enough for Councilwoman One to ask if he an hear her. He is based on The Kingpin and Tobias Whale.

Red Death (voiced by Clancy Brown): A veteran rank-10 supervillain who only arches his nemeses on one day a year. He has the appearance of a skinless red man, but in spite of his terrifying visage and reputation, he is actually a kind, gentle man who is a loving husband to a normal wife and father to a daughter who looks like him. However, when arching or in times of anger or other elevated emotion, he slips into an evil persona - signified by his skin darkening, eyes turning yellow and voice deepening - with no hesitation to kill; his apparent preferred method of killing is vaporization, and he is known to kill every time he arches in order to maximize his time spent with his family. He has balanced his civilian and supervillain lives and as such is able to switch between personas largely at will. Red Death is aware of The Monarch's reputation and knows him well enough to immediately identify the Blue Morpho as him; upon this discovery, he gives The Monarch advice about balancing family life and work as a supervillain as he was also once obsessed with a super-scientist nemesis until he realized he was neglecting his family and himself, and also tells him that rules allow villains to do what they do and if he follows the rules, he will get his chance to arch Dr. Venture once again. He agrees to keep The Monarch's identity as the Blue Morpho a secret in exchange for 21 allowing him to the last of the villains held hostage in a dungeon beneath the Morpho Cave. In season 7, it is revealed that Red Death was a member of a gang of young Guild villains at the beginning of his career in the 1980s, a group that also included the future Councilman 1, Vendata. Their group traveled to Gargantua-1 to carry out an unauthorized arching of Jonas Venture, only for the plan to go wrong and cause the death of all aboard the station in what would become known as the Movie Night Massacre. Red Death, Vendata and the others nearly faced execution for their disloyalty but the Sovereign ultimately chose to frame S.P.H.I.N.X., triggering the Pyramid Wars of 1987. In "The Rorqual Affair" he requests a seat on the Council in exchange for capturing the Blue Morpho and subsequently accepts the position in "The Terminus Mandate."

Brick Frog: A villain in a frog costume whose "superpower" is throwing bricks carried in a satchel, which even he recognizes is a useless ability. He first appears as an applicant to the Revenge Society in "Bright Lights, Dean City", but is rejected almost instantly upon his arrival. Subsequently, he makes cameo appearances in several other episodes. He is seen in Don Hell's club in "Bot Seeks Bot", revealing that he has become a Guild member, and at the meeting of the remaining Guild in "Hostile Makeover". He is also seen in Battleaxe's bar in "Tanks for Nuthin'," and at the Doom Factory's party in VenTech Tower in "It Happening One Night". He later appears at the Guild meeting regarding the Blue Morpho's activity in "The Rorqual Affair."

Scare Bear: A mysterious villain who is always seen wearing a bloody bear costume and holding a knife. As it never speaks, its gender is unknown. It first appeared as an applicant to the Revenge Society in "Bright Lights, Dean City," where it entered Professor Impossible's office without notice and frightened the Revenge Society leadership. It later became a part of the Guild, appearing in the background at various events before having a larger role in "The Forecast Manufacturer," where it saved an injured Hank from dying in a blizzard and brought him to Dean's dorm, where Sirena was cheating on Hank with Dean. How it knew Sirena was Hank's girlfriend and would be at the dorm with Dean remains unclear.

Flying Squid (voiced by Bill Hader): A squid-themed supervillain who first realizes the costume Shoreleave is wearing in the bar belongs to missing Guild member Sri Lankan Devil Bird. He then saves Dr. Venture from Don Hell by contacting The Monarch and Dr. Mrs. The Monarch to have them use guild law to intervene in the proceedings.

Vespertina (voiced by Paget Brewster): A floral-themed supervillain, named after vespertine flowers, who attempts to hit on Shoreleave in his Red-Throated Loon get up, but his campness turns her off.

Sri Lankan Devil Bird: A four-armed supervillain who attempts to arch Dr. Venture during the third-season episode "The Doctor Is Sin". Brock kills him swiftly. His costume is later used by Shoreleave to enter Don Hell's night club under the name "Red-Throated Loon", but Flying Squid identifies it as the costume of his friend.

Sunsational (voiced by Doc Hammer): A solar system-themed supervillain who associates with a group of henchmen each themed after one of the planets, with himself being the sun.

Galacticon: A robotic supervillain akin to Galactus. O.S.I. disguises Ghost Robot as Galacticon to go on a date with Vendata. Don Hell notes that the real Galacticon always comes to his club to pick up a new john, noting that he is into bears. The real Galacticon later appears at the club, causing problems with O.S.I.'s plans.

Haranguetan (voiced by Steven Rattazzi): A brutish supervillain with a preference for hand-to-hand violence. He is defeated by Warriana after injuring Sgt. Hatred and arguing with Brock. Later on, he returns to arch Dr. Venture again, only to become an unwitting test subject for Venture's "God Gas." The gas induces a violent hallucination in him, in which he sees Venture and Billy as demonic figures. While attacking Billy, he was confronted by The Monarch and 21 in their Blue Morpho and Kano alter-egos; 21 rescued Billy and knocked Haranguetan into a pit, killing him.

Battleaxe (voiced by Barbara Rosenblat): Haranguetan's widow and a supervillain in her own right, who owns and manages a pub. When informed by Dr. Mrs. The Monarch of her husband's death, she becomes emotional and suits up in her villain costume and makeup to retrieve his vehicle, the Haranguetank, from impound. After doing so she becomes intoxicated and begins driving to confront Dr. Venture, whom she believes to be the Blue Morpho, only to hit Think Tank and drive into the same pit where Haranguetan died. Though seemingly killed alongside Think Tank, she is later revealed to have survived and returned to running her pub.

Copy-Cat (voiced by Toby Huss): A New York-based supervillain with the ability to produce duplicates of himself. He is smooth and womanizing, with no concern for the marital status of the objects of his interest. He attempts to seduce Dr. Mrs. The Monarch at Wide Wale's party and uses his powers along with The Monarch's stolen costume to frame him for illegally arching Dr. Venture. Despite failing in his seduction, he succeeds in increasing the rift between her and The Monarch. Though unconfirmed to be him, a similar looking man appears in All This and Gargantua-2 as the lounge singer promoted for Gargantua-2's casino. He is a parody of Multiple Man and Dean Martin.

Dr. Nidaba/Think Tank (voiced by Jeffrey Wright): A genius supervillain who works as a professor of philosophy in his civilian persona, whose class is attended by both Dean Venture and Brown Widow. Upon receiving permission to arch Dr. Venture, he swiftly deduces that Dean is distracted from his classes by his home life and advises him to try and avoid his home situation, as he does not want to lose his best student. Later, donning a purple, tank-shaped suit of armor that grants him various abilities - such as the ability to ride up walls, project barriers and shoot laser projectiles - he attacks Venture, only for his plans to play chess fail when Venture informs him he does not play the game. He fights Brock and temporarily gets the upper hand, before Warriana - who has some unspecified (but very negative) history with him - appears and helps Brock destroy his armor. He is severely injured when hit by Battleaxe in the Haranguetank shortly afterward, though he is later revealed to be alive, and in a coma in The High Cost of Loathing. He is a parody of MODOK.

The Doom Factory: An avant-garde team of supervillains based on Andy Warhol and the Warhol Superstars as well as the Legion of Doom. Their M.O. is to throw lavish parties at the homes of their arches while quietly stealing all of their possessions. Their headquarters is a flying saucer beneath the Gowanus Canal in Brooklyn. Their headquarters was blown up in midair by The Monarch after they had just finished robbing Dr. Venture, killing them all at once.

Wes Warhammer (voiced by Chris McCulloch): The leader of the Doom Factory, based on Andy Warhol and Lex Luthor.

Frigid is a reference to Factory member Brigid Berlin. She is physically patterned after, and has the freezing powers of, Captain Cold.

Eenie-Meanie: A tiny, fairy-like villainess. Her name is a reference to Factory member Edie Sedgwick; her size-reducing powers are those of Bumblebee (a possible error in writing; Bumblebee is a heroic member of the Doom Patrol, and has never been a villain).

Serpentine is a name reference to Factory member Ondine, and has the loquacity of Riddler.

Hard Candy is a name reference to Factory member Candy Darling. This particular character actually appears to be a pastiche of two characters at the same time: while his skin seems to have the angular, multi-faceted appearance of Bizarro, his face strongly looks like that of The Joker (he also constantly cracks jokes).

She-Hemoth is a reference to Holly Woodlawn in terms of appearance, but her size-increasing power and appearance is that of Giganta.

Gerard the Gorilla takes his moniker from Factory member Gerard Malanga; he demonstrates no super powers in the episode, he physically resembles Gorilla Grodd.

Trashenstein is a reference to Factory member Joe Dallesandro: a pastiche of the titles of the movies for which he is most famously known, ''Flesh for Frankenstein'' and Trash. His mindless rage and monosyllabic grunting mirrors that of Solomon Grundy, even though his physical appearance is that of Frankenstein's Monster.

Black Maria is a reference to Factory member Paul Morrissey, while his appearance is an almost exact duplicate of longtime DC Comics supervillain and Legion of Doom member Black Manta mixed with a Polaroid Polavision film camera.

Ultra Violent is named after Factory member Ultra Violet; she physically resembles, and demonstrates the powers of Star Sapphire.

Billy Maim borrows his name from Factory member Billy Name, and while he does not seem to physically resemble any Legion of Doom member, his retractable finger claws are reminiscent of LoD mainstay Cheetah.

Col. Lloyd Venture (voiced by Christopher McCulloch): Grandfather of Dr. Jonas Venture, Sr., great-grandfather to Dr. Thaddeus "Rusty" Venture and Dr. Jonas Venture, Jr., and great-great grandfather to Hank and Dean, Col. Venture was the leader of the Guild (which at the time was not known as "The Guild of Calamitous Intent"). The Guild was a group set up to protect the Orb from falling into the wrong hands. It is initially believed that he is killed during his attempt to use the Orb by his bodyguard, but it is proven wrong in a later flashback.

Eugen Sandow (voiced by Paul Boocock): Famed German bodybuilder who served as Col. Venture's O.S.I. appointed bodyguard. In the flashbacks during the episode "Orb", he intimates in his phonograph diaries that he killed Col. Venture for attempting to discover the secrets of the Orb, the true purpose of O.S.I.'s watch over the Venture family, but in "The Revenge Society", it is revealed that he only broke the Orb and both he and Col. Venture hid this from their descendents and later bodyguards

Aleister Crowley (voiced by Steven Rattazzi): Famed British occultist who sought to use the Orb for his own ends, believing that he had a right to it as the Orb's most recent owner, but was later forcibly ejected from the Guild's zeppelin for doing so.

Fantômas (voiced by Christopher McCulloch): Famed (fictional) French gentleman thief and ancestor of Phantom Limb who wants to use the Orb to rule the world. He is later kicked out of the Guild, and forms his own Guild of Calamitous Intent by recruiting Buddy Holly (assumed to be present day Red Mantle) and the Big Bopper (present day Dragoon) by attempting to convince them that the sousaphone was an instrument that belonged in rock music.

Oscar Wilde (voiced by James Urbaniak): Famed Irish poet who upon Fantômas' suggestion to use the Orb for evil, denounces that the Guild should not be a "Guild of Calamitous Intent".

Samuel Clemens (voiced by Paul Boocock): Famed American author and member of the original Guild who alerts fellow members that they are being chased by Nicola Tesla and his cadre of Avon Ladies.

A new, independent organization of villains set up primarily to oppose the Guild of Calamitous Intent; as such, a number of its members have had unpleasant dealings with the Guild in the past. Its founder is Phantom Limb, who initially created the society as his "team" to obtain the ORB for use against the Guild; however, this version of the Revenge Society was merely Phantom Limb himself along with a coffee mug named Wisdom, a toaster named Chuck, and a shoe called Lady Nightshade that he believed (possibly deludedly) were real people. After escaping Guild custody later on, Phantom Limb teamed up with Richard Impossible to found the current Revenge Society, which has since had quick success in the field of villainy (though there are only six members) and they fail to kill Dr. Venture, twice in "Bright Light, Dean City". The group has effectively been broken up as of "All this and Gargantua-2".

The Phantom Limb (Hamilton G. Fantomos) (voiced by James Urbaniak): A villain with invisible arms and legs. He is arguably the most competent villain seen thus far in the Venture Brothers universe, however he seems largely indifferent to the Ventures themselves. Although he is quite cunning and ruthless, he is also one of the more culturally refined characters in the show, judging from his interest in Persian rugs and fine cheeses. He framed The Monarch for murder and attempted to foil The Monarch's escape plot, ostensibly because he wanted Dr. Girlfriend all to himself. It was later revealed in season 2 that the framing of The Monarch was simply part of a larger picture to lure out and kill The Sovereign and seize the leadership of the Guild of Calamitous Intent. Despite his intellect, he often comes off as pretentious, and at times clueless about the repercussions of his action - as if he's too far into his 'role' to understand what he's doing. At the end of season 2, he seems to have escaped, although minus an invisible leg and arm (and perhaps another "limb"). His name and invisible limbs are references to the phantom limb syndrome experienced by amputees. The name and purple costume are also references to the comic book and comic strip hero The Phantom. It is revealed in episode three of season three that he was originally professor at a state college and had tiny deformed arms and legs, resulting in him being disowned by the Fantomas family and thus losing his "right" to inherit the title of Sovereign. When Billy Quizboy was sent in by O.S.I. to spy on him, Fantomas made Billy his lab assistant, thinking he possessed a brilliant mind. During an experiment to turn his limbs to normal size, a malfunction occurred which turned Fantomas' limbs not only to normal size, but also invisible, and endowed him with the ability to kill with a mere touch. He later returns in "The Revenge Society" with the name Revenge, sporting a new costume and white hair caused by the trauma of losing several limbs and an implied castration. After leaving the guild, he appeared to have gone insane, forming a "team" consisting of Wisdom (a coffee cup), Chuck (a toaster), and Lady Nightshade (Dr. Mrs. The Monarch's black Ferragamo shoe). In the same episode he steals the ORB from Dr. Venture, and during the climax he attempted to activate it, believing it would give him the upper hand. Moments later, nothing happened. In a flashback it is shown that the ORB was broken by Sandow (the bodyguard of Venture's grandfather) who chose that option as opposed to killing Venture, as he was initially instructed. Phantom Limb, distraught from losing the power of the ORB, kneels defeated before David Bowie and his Guild underlings and is promptly captured. After a few months in Guild custody, he escapes and founds a new incarnation of the Revenge Society; the first recruits of his new organization are a now-villainous Professor Impossible and Baron Ünderbheit. He betrays the Revenge Society's heist plan to the Sovereign in "All this and Gargantua-2" in exchange for its members being made Councilmen and is ultimately ejected by them for his secret-keeping, becoming a member of the New Council of 13.

Professor Richard Impossible (voiced by Stephen Colbert in seasons 1, 2, and "All This and Gargantua-2" Peter McCulloch in "The Terrible Secret of Turtle Bay", Christopher McCulloch in season 3, and Bill Hader in season 4): Nicknamed Dicky. Founder of Impossible Industries, a major government contractor, and former professor to Dr. Venture, Mr. White, and Billy Quizboy. He holds science and the pursuit of knowledge in a much higher regard than he does his wife or other people; at times this has made itself manifest as homicidal ruthlessness, though most of the time he's simply out of touch. Impossible and his cohorts are a parody of the Fantastic Four: an experiment with cosmic radiation gave them each strange abilities (this parody is referenced explicitly in the episode "Love Bheits" when it is mentioned that the Impossibles beat the Ventures in a costume contest by dressing as the Fantastic Four). Richard can stretch his body like rubber, similar to Mister Fantastic, and seems to use this power to make himself appear taller. The other members of his family have useless parodies of the other members' powers. A disheveled, depressed Richard Impossible is seen in "Pomp & Circuitry," having spent time since the party in terrible condition, being recruited by the Phantom Limb for his help (citing their time together in Dr. Venture's Boy's Brigade) to gain revenge on the Guild, and in the end, forming a new Guild with Phantom Limb. Richard then takes on the supervillain moniker Professor Incorrigible, but quits when he realizes his son needs him to be a father and leaves Gargantua-2 with his ex-wife and son.

Baron Werner Ünderbheit (voiced by T. Ryder Smith): A noted member of the Guild of Calamitous Intent and former tyrant dictator of Ünderland. He wears a prosthetic metal jaw and speaks in a thick, pseudo-German accent. He blames Dr. Venture for the loss of his jaw; as he says, "In my country, a lab-partnership is a sacred trust. One is always supposed to look out for one's lab-partner! Venture... did not." It has since been revealed that the explosion that disfigured Ünderbheit was actually caused by The Monarch, in an attempt to kill Dr. Venture. Baron Ünderbheit is a parody of Doctor Doom and Apocalypse, and has been jokingly identified as such in the context of show (e.g. The Monarch referred to him as "that dime store Doctor Doom"). Ünderland is a sovereign nation that shares at least one border with Michigan. Ünderland is a parody of Latveria and other fictional comic-book countries, which play on the reader's relative lack of knowledge of geography. After his deposing, he is seen in "Pomp and Circuitry" panhandling outside of Impossible Industries, and again in the post-credits sequence asking to join Phantom Limb and Professor Impossible's new Guild. He is presumed dead after Gargantua-2 exploded.

Manservant (voiced by Christopher McCulloch): Baron Ünderbheit's long-time personal servant, given to him as a birthday present from his mother while he was in college. He is so completely devoted to Ünderbheit that he almost seems to have no will of his own; he speaks in a zombie-like monotone somewhat reminiscent of Peter Lorre, and always appears to be staring into space. He is seen in "Pomp and Circuitry" with Baron Underbheit, panhandling outside of Impossible Industries, and by his side when the Baron tries joining Phantom Limb and Impossible's new Guild. In "Bright Lights, Dean City" he appears briefly with the Revenge Society in a new costume before Ünderbheit, to show loyalty to the Society, seemingly breaks his neck, killing him. (The Society then mentions they just wanted him to sign a pledge).

Fat Chance (voiced by Christopher McCulloch): A supervillain recruited into the Revenge Society to fill up missing archetypical positions. After a scientific accident, Fat Chance's duodenum now contains a portal to another dimension from which he pulls objects that always seem to help him. In the Revenge Society's attempt to kill Dr. Venture, he trips and falls on Venture, sending him to the alternate dimension. He is presumed dead after Gargantua-2 exploded.

Lyndon Bee (voiced by Christopher McCulloch) and Ladyhawk Johnson (voiced by Mia Barron): A pair of supervillains inducted into the Revenge Society. They are parodies of President Lyndon B. Johnson, his wife First Lady Claudia Alta "Lady Bird" Taylor Johnson, and the film Ladyhawke; during the day Lyndon Bee transforms into a bee and at night Ladyhawk transforms into a hawk, and they are cursed to never be together except during an eclipse. Their whereabouts following their initial acceptance into the Revenge Society are unclear; they appear to have been removed by Killinger in favor of Radical Left and Zero.

Radical Left (voiced by Christopher McCulloch): A supervillain imprisoned at Dunwitch Asylum who has half of his body severely disfigured. Based on DC comics villain Two-Face, his personality is split between "Radical" anarchist ideas and peaceful desires more akin to a common 50's suburbanite. He is later seen as a member of the Revenge Society and later the New Council, in "All This and Gargantua-2". It is revealed in season 7 that Radical Left absorbed his nemesis Right Wing in a past encounter, meaning they each share one half of a full body. This explains Radical Left's inability to agree with himself.

Zero (Scott Hall) (voiced by Christopher McCulloch): Originally Number One in The Monarch's forces, he is brutally beaten by Brock Samson in a stealth mission on Spider-Skull Island after his adherence to cliches while sabotaging the island caught Brock's attention. Later, he takes the name Zero, and with the original Captain Sunshine, kidnaps the world's sidekicks to pit them in battle against each other, only to be stopped by a rebellion led by Gary. He joins the Revenge Society in their robbery of Gargantua-2, but his genre blindness ultimately leads to his death, as he becomes so caught up in killing Brock that he spends minutes monologuing to him and thus allows Amber Gold to disarm him, giving Brock the chance to snap his neck.

Ünderland is a micronation smaller than the state of Delaware and located near Michigan. Once led by Baron Werner Ünderbheit in a dictatorship, he ruled the land and had a forced conscription for all men age 18 and a forced euthanasia at 40. Ünderland also had no prisons, as all crimes are subject to the death penalty. As a result of "Love Bheits", Ünderbheit is deposed and Ünderland becomes a democratic society.

Girl Hitler (voiced by Mia Barron): Formerly one of Baron Ünderbheit's senior advisers, she (along with Catclops and Manic 8-ball) were "executed" for betraying Ünderbheit's confidence, although all three survived. Since Baron Ünderbheit's removal from power, she has become Ünderland's democratically elected president, turning Ünderland into a progressive society that has a female and Hitler president. As her name suggests, she resembles Adolf Hitler, complete with toothbrush moustache.

Catclops (voiced by James Urbaniak): A cyclops with a cat's face (itself wearing an eyepatch since his second appearance) in the place of an eye and a tail protruding from the back of his head. After their "execution" by tiger-bombs, he and Girl Hitler fled underground, where they led an ineffectual group of freedom fighters. After Ünderland's liberation, he proposed to Girl Hitler.

Manic 8-ball (unvoiced): He is a human with the powers of a magic 8-ball. He was "executed" by Baron Ünderbheit for treason along with Catclops and Girl Hitler. Despite surviving the combination of tiger attack and explosion, he was captured and remained a prisoner of Ünderbheit, who used his eight-ball power for advice. Lacking a mouth, he never speaks, instead using the 8-ball messages on his chest to answer yes or no questions (except for one message, in which he calls Ünderbheit an "asshole").

Eunuchs (voiced by Christopher McCulloch and James Urbaniak): A pair of femme and now castrated homosexuals who work under Baron Ünderbheit to prepare Dawn (Dean Venture) for the Baron's wedding. The thinner of the two was actually a college student from Detroit who took a semester abroad to Ünderland before being captured and conscripted as a court eunuch. He discovers that Dean is actually a boy but keeps the secret to embarrass Ünderbheit.

King Gorilla (voiced by Christopher McCulloch): A talking, homosexualgorilla who befriended The Monarch while in jail. King Gorilla was a member of the Guild of Calamitous Intent until his imprisonment for brutal murder and rape (in that order) of Mötley Crüe lead singer Vince Neil during a reality TV show, defending himself by stating "I only sodomized half of him". Because of his high-profile crime, the Guild turned its back on King Gorilla and has led to the villain becoming bitter and cynical towards the Guild. After kidnapping and attempting to rape The Monarch (The Monarch's feminine qualities turned him off before the act), he was moved enough by The Monarch's quest to regain Dr. Girlfriend's love that he assisted in the fellow villain's escape from prison. When he is hesitant to help The Monarch before he does, The Monarch parodies a quote from The Tragedy of Julius Caesar, saying, "Et tu, King Gorilla?" His ability to talk and walk upright is not explained, and he has an obsession with Tarzan (Christopher McCulloch has suggested that he somehow houses and raises multiple Tarzans in his cell or the common area of the prison). King Gorilla mirrors the many super gorillas and apes that exist in comics (particularly in the DC Universe), which include several heroic ones like Solovar, Detective Chimp or Congorilla, but are mostly villains like Monsieur Mallah (who also talks and is homosexual), Gorilla Grodd (a talking genius level gorilla, enemy of the Flash and member of the Secret Society of Super Villains), Ultra-Humanite, Titano, The Mod Gorilla Boss, Gorilla Boss, Jackanapes, etc. Though it was believed at first that King Gorilla had been killed off screen by Phantom Limb, Christopher McCulloch's LiveJournal has revealed he was supposed to return, free from prison, in the second half of the fourth season. He has apparently been released for medical reasons, as he now apparently has lung cancer (implied by the angry faces at Monarch's gift, cigarettes, when Monarch was unaware of the illness). In "The Silent Partners", King Gorilla is killed in his hospital bed by the Investors. It is revealed he made a deal with Monstroso via the Investors, securing an early release from prison in exchange for King Gorilla donating his heart to Monstroso after his death.

Mr. Monday (voiced by Christopher McCulloch): An upperclass-esque villain with a monocle, obsessed with Monday. The character very much resembles the Detective Comics character Calendar Man. When The Monarch is planning his breakout for that night, Mr. Monday insists "Can't we wait until Monday?" and uses words such as "Mondaylicious!" Mr. Monday is released from prison by Phantom Limb, only to be hunted by him on his private grounds to make a point to The Monarch in Showdown at Cremation Creek (Part I). He is killed by Phantom Limb in this scene.

Tigeriffic (voiced by Paul Boocock) A former supervillain with massive strength and tiger-like abilities. When imprisoned, his costume was confiscated, which apparently is where all his powers come from. When The Monarch assigns him to pull off the gate during the breakout, Tigeriffic informs him that he is powerless without the costume. The Monarch is shocked, as he assumed he was "Raised by tigers, like Moogli." "It's Mowgli...and that was wolves...and still no!"

White Noise (voiced by Brendon Small) A smoking, racist former television repair-man, White Noise was transformed while repairing a TV that was still plugged into a live socket. He is concerned about The Monarch's criminal organization being "racially mixed", and doesn't want his pure white blood to be muddied. The Monarch then questions whether he even has blood, and how he knows he's even white. He speaks with a Southern dialect. During The Monarch's escape, he was supposed to aid by taking out the guards, along with Dr. Septapus. He is also hunted and fatally shot by Phantom Limb on his private grounds.

Dr. Septapus (voiced by Christopher McCulloch): Another one of The Monarch's criminal cohorts while in prison, Dr. Septapus has seven limbs on his body. Four arms on his sides, one arm from his chest, and two legs. He is loosely based on the Marvel Comics character, Dr. Octopus. During The Monarch's escape, he was supposed to aid by taking out the guards, along with White Noise. He is released from prison, only to be hunted by Phantom Limb on his private grounds. He is shot down from a tree, and then shot again on the ground.

Tiny Joseph (voiced by Doc Hammer): Although he originally appeared as one of The Monarch's henchmen in a dream sequence in "A Very Venture Christmas", he later appeared as The Monarch's cellmate. He is only a few inches tall, and inscribes a message upon a Microdot, which is to be carried out by a butterfly for The Monarch. He was also used as a projectile in The Monarch's makeshift prison dartgun.

Teddy (voiced by Christopher McCulloch): A criminally insane supervillain with severe burns who once provided the voice for a Teddy Ruxpin-like toy, imprisoned in the Dunwitch Asylum for the Criminally Insane after hugging Ronald Reagan too hard. The boys and Hatred first use the toy (along with an Optimus Prime mask and an Incredible Hulk mask) to trick their father into thinking he has been kidnapped by Zeus during the events of "Any Which Way but Zeus", and then Hank and Dermott use the same toy to trick their father into thinking he is still talking to Teddy in "Momma's Boys" by using a prepaid cellphone to keep him occupied while they sneak out of the house. When Venture discovers part of the ruse, he assumes Teddy is in danger. Hank, Dermott, Gary, and H.E.L.P.eR try to get into Dunwitch to talk to the original Teddy, but fall into Myra Brandish's coup attempt. Teddy later escapes and saves Dr. Venture and Sgt. Hatred from certain death when their car falls into a ravine on the way to "Bygolly Gulch".

Cuckoo Clocker (voiced by Christoper McCulloch): A supervillain imprisoned at Dunwitch Asylum who has a cuckoo clock door in his head.

Big Time: A supervillain imprisoned at Dunwitch Asylum who has a clock face tattooed on his face and his moustache resembles two clock hands. Both he and Myra Brandish believe he has powers over time.

Maybe Man (voiced by Christopher McCulloch): A supervillain imprisoned at Dunwitch Asylum who Myra Brandish asks to place Dean in her womb so she may finally give birth to him, although he only responds with "maybe".

The Fraternity of Torment is one of a handful of supervillain organizations other than the Guild of Calamitous Intent. The group was largely made up of disenfranchised men shunned by society for their various physical defects. They were frequently the antagonists to Team Venture during the 1960s, and it is shown that Jonas and his team often seemed to merely be tormenting and bullying them for fun rather than fighting them out of any sense of justice. The remnants of the original group appear in "Now Museum, Now You Don't", but it is stated they still have some level of presence in the world of organized supervillainy alongside the "Peril Partnership".

Scaramantula (voiced by Toby Huss): An Italian spider-themed supervillain,themed after the James Bond villain Scaramanga. He has eight fingers on his right hand and a partial spider mask on his face complimented by his eyebrows and moustache as a full set of eight legs. He owned Spider Skull Island until an unsuccessful kidnapping of Rusty Venture results in their defeat by Team Venture, as Dr. Venture has infiltrated the group posing as "Dr. Fanadragon" whose backstory claimed a supernumerary nipple caused exclusion in his hometown of "Japaninawa". After Dr. Venture reveals his identity, the Fraternity is defeated by Team Venture and Scaramantula escaped, and set off a self-destruct sequence that ultimately failed, resulting in Spider Skull Island's annexation into Venture Industries. In the present day, Scaramantula has retired from supervillainy and is in top shape having exercised on Spider Skull Island's escape path many times. After seeing what has been done to his former home, he assists Brainulo in taking revenge, and ultimately escapes another death at the hands of the self-destruct sequence.

Brainulo (voiced by Christopher McCulloch): A supervillain from a thousand years in the future claimed to have been trapped in the year 1969 after Dr. Jonas Venture destroyed his means of returning. With his superior intellect and mental powers, he controlled a giant robot known as Futuro. During the attack on Spider Skull Island by the original Team Venture, Brainulo took control of Futuro, but the Humongoloid knocks it over, crushing Brainulo. In the present day, Brainulo is revealed to be a paraplegic and it appears he has become senile, but the senility is all an act to take revenge on Dr. Venture and his offspring. He preys on the insecurities and fears of those at the Jonas Venture Museum's opening party, hoping to cause a riot, but when he fails he attempts to take control of Futuro one last time, but the attempt shorts his own brain, resulting in actual senility. He turns up again in the lobby of Impossible Industries in "Bright Lights, Dean City" as an apparent applicant to the Revenge Society; however, given that he is merely sitting still and staring, he may have simply wandered in.

Manotaur: A supervillain themed after the Minotaur, possessing superstrength having been made an outcast due to his size. During the flashback in "Shadowman 9: In the Cradle of Destiny", The Monarch claimed to be "Manotaur" to avoid retaliation from Phantom Limb after he seduced Dr. Girlfriend. In the end of the episode, it is revealed the Manotaur is real and had since retired into a job with the MTA whereupon he is killed by the still living Phantom Limb.

The Peril Partnership is another supervillain union based out of Toronto, Ontario, Canada. It is one of several rival organizations to the Guild of Calamitous Intent. Its members can be distinguished by their wearing the letters 'PP.' In season 7, it is revealed that the Peril Partnership has infiltrated the Guild.

Tiger Shark (voiced by Christopher McCulloch): A shark-themed supervillain who is the only known member of the Peril Partnership. He appears in "Any Which Way But Zeus" to participate in the think tank to find everyone's kidnapped henchmen and sidekicks. He reveals he previously fought Brock Samson during Samson's time in O.S.I., though his vendetta is more personal since he found Brock in bed with his wife. Brock half-heartedly apologizes and hints his wife lied to him about being married.

Originally a terrorist organization (an homage to G.I. Joe's Cobra) that was the primary adversary of the O.S.I. 20 years ago until its defeat in the Pyramid Wars of 1987. The Pyramid Wars began when S.P.H.I.N.X. seemingly claimed credit for the Movie Night Massacre on Gargantua-1, in which Jonas Venture Sr. and many others perished, but the organization was actually framed by the Sovereign using S.P.H.I.N.X. Commander's form. Several members of the O.S.I. who were disillusioned with its ineffectual bureaucracy decided take up the S.P.H.I.N.X. mantle, along with their leftover equipment, to create an organization to deal with rogue supervillains (those who do not abide by the rules of organized villainy mandated by institutions like the Guild of Calamitous Intent). At the end of season 4 and the beginning of season 5, the members of S.P.H.I.N.X. who were formerly O.S.I. agents are redrafted into O.S.I., leaving the former Henchman 21 as the only S.P.H.I.N.X. operative. Gary tries to recruit new members, and accidentally reunites the original S.P.H.I.N.X. members. Knowing that their S.P.H.I.N.X. loyalty chips will soon dissolve and kill them, they dedicate themselves to a final suicide attack against O.S.I. S.P.H.I.N.X.'s rented headquarters space within the Venture compound is blown up in the season 5 episode "S.P.H.I.N.X. Rising", forcing Gary to live in the Venture's backyard. The original remaining S.P.H.I.N.X. members are:

Michael/SPHINX Commander (voiced by Christopher McCulloch): A parody of Cobra Commander, SPHINX Commander is a fairly tall man who can't control the volume of his voice. He has been stalking his former lover Theresa, the Countess. Gary forbids him to use his former name "SPHINX Commander" because Gary is now the leader, so Michael calls himself "Mister Daddy Warlord of the Children of the Corn". He later usurps Gary's position and kidnaps Hank, who is using the Countess' old power suit. He is later killed by Brock after refusing to hand over Hank.

Theresa/The Countess: SPHINX Commander's former second-in-command and lover, a parody of the Baroness. Her powered armor suit grants its wearer enhanced strength and mobility. Hank adopts the suit, but since it was designed for the Countess it makes Hank look and move like a woman. It has a feature that prevents the wearer from harming the SPHINX Commander. After SPHINX is defeated, Hank keeps the power suit and wears it all the time. Molotov Cocktease steals the suit in "O.S.I. Love You", and it is destroyed by Brock Samson in order to fake Molotov's death.

Wind Song (voiced by Tim Meadows): A parody of Storm Shadow, Wind Song is an African American ninja member of the original S.P.H.I.N.X. He has taken to forming a family and wearing sweaters inspired by Cliff Huxtable during his retirement.

Diamond Backdraft (voiced by Larry Murphy): A former member of S.P.H.I.N.X. who was the group's flamethrower and snake-handling operative.

Storm Front (voiced by Christopher McCulloch): A weather controlling supervillain who protests to having to have his powers temporarily taken away for the think tank in "Any Which Way But Zeus". He claims he will not harm anyone, as his powers are purely precipitation based.

Crime-o-dile: An unseen crocodile-themed supervillain previously killed by Captain Sunshine after he fell into his own crock-pit that was set on fire. A henchman appears in a support group attended by 21 and 24 after the imprisonment of The Monarch.

Scorpio (voiced by Christopher McCulloch): Another member of Captain Sunshine's rogues gallery who is scorpion-themed. He later appears in Sgt. Hatred's old home in Malice, having become Princess Tinyfeet's new lover.

Molotov Cocktease (voiced by Mia Barron): a highly trained assassin and sometime-ally, sometime-rival to Brock Samson, as well as his love interest until her apparent death at the end of the episode "Operation P.R.O.M." Despite, or perhaps because of their often-violent history, she held Brock in very high regard, although she disdained his loyalty to the Ventures. She was an ex-Soviet agent who made a living as a mercenary. She shared a somewhat sadomasochistic relationship with Brock, who has referred to her as "the only woman [he has] ever loved." She unfailingly wore a chastity belt (her father's dying wish) until the end of the fourth season, when she told Brock she was "taken" by Monstroso. Her name is a play on the phrases "Molotov cocktail" and "cock tease." In some Venture Bros. related artwork, her last name is spelled "Coqtiz," though "Cocktease" has become the official spelling. Her name is also a reference to Bond girls with improbably provocative names, such as Pussy Galore. She appears to commit suicide at the end of season four, by falling off a tall cliff in front of Brock Samson. However, in the fifth-season premiere, Brock investigates the site and finds evidence that Molotov may have faked her death and is in hiding with Monstroso. She and Monstroso are captured by O.S.I. in "O.S.I. Love You", and during interrogations Brock reveals that he first met her when she was a gymnast at the inaugural Goodwill Games and her father was a mercenary they had been sent to kill before he assassinated Mikhail Gorbachev, but he discovers she too was a mercenary who killed Brock's partner at the time. She escapes custody and goes on a rampage throughout O.S.I.'s hovering headquarters, killing several operatives and stealing Hank's power suit. In the end, just as Brock is about to kill her, Col. Gathers reveals she has been hired by him to root out double agents in O.S.I. and to test their security. To prevent this knowledge from falling into the hands of the Misters, they fake Molotov's death.

Colonel Bud Manstrong (voiced by Terrence Fleming): The former leader of the two-man crew of the space station Gargantua-1. Manstrong takes a strong moral stance on most issues, and is strictly sexually abstinent, which his mother attributes to his similarly-abstinent father having been a larger influence on the young Bud than her. He also has the moral stances and vocabulary of a man from the 1950s to the 1960s (he refers to Brock as a Mandingo, an outmoded racist term). Although he is very willful in most situations, he wilts under attention from his often inebriated and oversexed mother. His forbearance of sex puts a great deal of strain on his relationship with cosmonaut Lieutenant Anna Baldavich, his love interest and fellow crew member aboard Gargantua-1. He is declared a hero when Gargantua-1 crashes on a wanted terrorist group in the episode "Guess Who's Coming to State Dinner?" whereupon he is offered a chance to run for the vice-presidency, which he turns down in horror upon learning of the president's sexual indiscretions (strongly satiric of the Clinton-Lewinsky affair, although the president resembles Lyndon Johnson physically and speaks in the manner of George W. Bush with similar public approval issues).

Lieutenant Anna Baldavich (voiced by Nina Hellman): Col. Manstrong's only companion and crew member on Gargantua-1. Baldavich is a Russian cosmonaut whose face is never shown, but it is suggested that it is extremely unattractive. However, this has not stopped Manstrong from falling in love with her, and she for him, but he will not return her advances for intimacy, which has caused Baldavich to become increasingly upset with him. To this end, she successfully seduces Brock, who demands that during sex she keep her helmet on, in order to both satisfy her urges and to make Bud jealous enough to force him to initiate sex with her. Instead, Bud completely gives up on his relationship with Anna, and pushes Brock to marry her due to his archaic beliefs. Manstrong reveals that her father invented the Mr. Mouth board game, and as a result she is quite wealthy. After the Ventures leave Gargantua-1, she and Manstrong seem to reconcile, but he still refuses to be intimate. As the space station fails for the last time and crashes into the Earth, Baldavich gives Manstrong a handjob, causing him to pass out, and she dies in the resultant crash, and is given a closed casket state funeral in Moscow.

The Master (voiced by H. Jon Benjamin): A shapeshifting, supernatural presence who lives in a black void accessible through a portal in Triana's closet, he is Dr. Orpheus's mentor. What he is, and therefore his gender, are never made clear, although he speaks in the same masculine voice regardless of his appearance, and is referred to by other characters using masculine pronouns. He is much more relaxed than Orpheus, and often chides his student for being extremely uptight. However, this attitude seems to be his method of imparting advice to his pupil; he convinces Orpheus to better himself by pointing out his flaws. He has called Orpheus his best student and seems to have a fondness for him, frequently letting Orpheus come to him for advice. He often takes on appearances that make it possible for him to perform erotic acts; his first appearance is as Cerberus, a form in which he entertains himself by allowing a head he cannot control to clean his genitals with its mouth. Later, he appears as the alleged horse that killed Catherine the Great to try to teach Orpheus a message about "biting off more than you can chew". At another point, he appeared as Orpheus' divorced wife Tatyana, and later as a proposed future version of Dean Venture to convince Triana to move away from home. In "A Very Venture Halloween", the Master appears to the society of magicians as Santa Claus.

Myra Brandish (voiced by Joanna Adler): First appearing in "I Know Why the Caged Bird Kills", Myra is a mentally unstable woman who is under the impression that she is Hank and Dean's mother, kidnapping the boys and eventually capturing Dr. Venture when she comes in contact with him as well, revealing that she is also his former O.S.I. bodyguard. After being subdued by Brock, he states that Myra is a former cast member of American Gladiators nicknamed "Power Cat" who checked herself into an insane asylum after the show was cancelled and began kidnapping the Ventures whenever she goes off her medication and breaks out. Venture, however, admits that he slept with her. During a flashback in "Shadowman 9: In the Cradle of Destiny", she is seen acting as Dr. Venture's bodyguard, saving him from an attack by The Monarch with loving eyes towards Venture. In a later flashback in "The Invisible Hand of Fate", Myra is seen being taken away by O.S.I., claiming she loves Dr. Venture, while he holds his toddler sons in his arms. It is in this episode that she is revealed to be working on Operation: Rusty's Blanket, an assignment that Brock receives later. Myra's next appearance is in the episode "Momma's Boys", where it is revealed she is incarcerated at the Dunwitch Asylum for the Criminally Insane and has been keeping in contact with Dean who believes she is his mother. She has charmed one of the guards and several other inmates under her thrall as "Momma" and has had Dean visit on Mother's Day so she may finally give birth to him, revealing to both Dean and Hank (who were visiting her and attempting a rescue respectively) that she is not their biological mother. Hank's declaration causes the other inmates to rebel, allowing for their escape. Elsewhere, Dr. Venture has confided to Sgt. Hatred that he tricked Myra into thinking she was the boys' mother in order to get her to babysit them for free.

General Manhowers (voiced by Christopher McCulloch): A general in the United States armed forces. Due to his high military rank, he is one of Dr. Venture's principal clients. He buys the Ooo Ray from Venture in the pilot episode. In later appearances, Gen. Manhowers realizes that Venture has not invented anything new in years, as in his latest foray to the compound during season 3's "The Doctor Is Sin". However, he does commission Venture to make an army of Venturesteins out of the murdered Ted and Sonny as well as some spoiled clones of the boys. When the original Venturestein revolts during season 5's "Venture Libre", he sends Venture to retrieve him, with a jPad armed to explode.

Princess Tinyfeet (voiced by Sue Gilad): Sgt. Hatred's wife, she is a Native American who bears a striking resemblance to the maiden on the Land O'Lakes logo. Sgt. Hatred loves her for her namesake tiny feet, these having been the saving grace from his pederasty. She only speaks one word in the series: "Maize". However, during the events of the two-part "The Family That Slays Together, Stays Together" it is revealed that she "wants to talk" with Sgt. Hatred, which he takes to mean she is ending their marriage, something Dr. Mrs. The Monarch corroborates. They separate, and in "Return to Malice", Dr. Venture discovers that Princess Tinyfeet is into bondage in a scene he narrates to Sgt. Hatred. This is later confirmed when The Monarch and Dr. Mrs. The Monarch kidnap her as a means to appease Sgt. Hatred, having already found her bound and gagged. Intent on reuniting with his wife, Sgt. Hatred takes her back to their marital home in Malice, only to discover she has been living with Scorpio.

Dr. Tara Quymn (voiced by Nina Hellman): Dr. Quymn is a superscientist and childhood friend of Dr. Rusty Venture, as her mother Mz. Quymn was well acquainted with Dr. Jonas Venture, and her stepfather is Colonel Gentleman. She meets up with Rusty when he goes to the Amazon to seek out a plant that might help with his erectile dysfunction while she is in the Amazon for more altruistic reasons, investigating as to whether or not the fruit known as Solomon's Heart can cure cancer. Her life closely parallels that of Dr. Venture, in that she is accompanied by a brutish bodyguard and has a set of twin children, although they are all women unlike Dr. Venture's all-male family unit. She and Rusty fall for each other, once more, but the alleged attack of the "Wereodile" exacerbates Dr. Quymn's epilepsy causing a seizure, a fact that horrifies Dr. Venture, and she begins to smoke a cigarette she has hidden away in a pendant around her neck. She has had a series of bad relationships, and Ginnie believes that this is just another. In the end, the two doctors end their respective relationships, but it is later revealed that Dr. Quymn's heart was broken by the short affair when Colonel Gentleman berates Rusty for hurting his stepdaughter, unaware of the true circumstances behind their breakup. It is suggested that Dr. Quymn is the half-sister of Dr. Venture, as the two closely resemble each other and Dr. Jonas Venture Sr., and Mz. Quymn were long involved in a romantic affair behind Colonel Gentleman's back.

Nancy & Drew Quymn (voiced by Nina Hellman and Joanna Adler): Dr. Quymn's identical twin daughters, who only differ in that Drew has a freckle on her nose. They go on mystery solving adventures, not unlike those of Hank and Dean. Hank falls in love with both of them, but both are instead enamoured with Dean who is oblivious to their attraction. They fight over who should have Dean, but they later decide to share him, but he is repulsed by the event as he believes the two to be "wereodiles". When Hank is revealed to have been circumcised by the Amazonian villagers threatened by the "Wereodile", the two suddenly lose interest in Dean. Hank later tries to ask them out for his and Dean's prom, to no avail. Their name comes from the fictional girl detective Nancy Drew.

Ginnie (voiced by Joanna Adler): Dr. Quymn's muscular bodyguard. Her sexuality is a source of jokes, as she resembles the butch lesbian archetype and constantly tries to convince Dr. Quymn to give up men. However, she still flirts with Brock, who is confused by her means of courtship which includes the use of double-entendres and sexual poses before rebuffing him when he pays attention to her. In the end, Ginnie reveals in her discussion to Dr. Quymn that she does not want to have to pick her back up from another broken relationship, showing that Quymn has been in a series of broken relationships. In the confusion, Dr. Venture asks for help and Brock comes to his assistance, resulting in an equally matched fight between Brock and Ginnie, who both show pleasure in the fight.

Venturestein (voiced by Christopher McCulloch): A former henchman of The Monarch killed by Brock and brought back to life by Dr. Venture's superscience in "¡Viva los Muertos!". Due to his initial attempt to strangle Dr. Venture, Brock caves in his skull and they have to find a replacement belonging to a deceased black man. His control over the English language is limited, at first, but he soon begins to learn how to compose more coherent sentences. Dr. Venture initially decides his Venturestein project should work in factories, using the boys' learning beds to teach Venturestein how to make shoes, but General Manhowers decides to buy 100 Venturesteins when he discovers they can be used as expendable soldiers, and filled with C-4. In "Venture Libre", it is revealed that during his time in the army, he and the Venturesteins are sent to quell a factory strike in Puerta Bahia, only for Venturestein to meet Jorge, the young Mexican boy who appeared in the instructional video he watched when he was first made, who teaches him how to speak better and also the teachings of Che Guevara. This leads Venturestein to liberate several other scientific experiments he has found in the Central American jungle, for some reason home to many evil scientists, and to form an "Abomi-Nation" where all such scientific experiments can call home. His loyalty to Dr. Venture, who he does not see as a horrible creator as the other scientific experiments do, and his friendship with Hank, as well as the death (and subsequent reanimation) of Congresswoman Marsha Backwood, lead to the successful formation of his "Abomi-Nation" and their formal entry into the United Nations. Venturestein is still seen as being able to properly make sneakers in his appearance.

Groovy Gang: A parody of the cast of Scooby-Doo and several infamous criminals who head to the Venture Compound to steal items for gas money.

Ted (voiced by Christopher McCulloch): The gang's charismatic and sociopathic leader, who often threatens the others (usually Patty and Sonny) with violence and the wrath of God. Upon spotting Dr. Byron Orpheus, he believes the Venture Compound to be a "Dracula factory". Ted is killed by Brock when he attempts to kill the man in self-defense, and he is used to make a new Venturestein, later seen to be one under the original Venturestein's command. He is a pastiche of Fred Jones and serial killer Ted Bundy.

Patty (voiced by Sue Gilad): The red-headed and relatively fashion-conscious member of the gang. It is hinted that Ted kidnapped her years ago, and she is now suffering from Stockholm syndrome. She runs away from the compound with Val after Ted, Sonny, and Groovy are killed. She is a pastiche of Daphne Blake and Patty Hearst, an heiress who was kidnapped by the Symbionese Liberation Army and then joined them in a series of crimes, during which time it is believed she suffered from Stockholm syndrome.

Val (voiced by Joanna Adler): The bespectacled brains of the group, who seems to be attracted to Patty and is aware of Ted's lies, but does nothing about them as they allow her to both take advantage of Patty's low self-esteem and abuse Sonny when he is at his most vulnerable. Despite her outspoken misandric belief system, she gets along with Ted quite well due to their shared desire for control over Patty and Sonny. She survives the events of the episode with Patty and runs away to parts unknown afterwards. She is a pastiche of Velma Dinkley and Valerie Solanas, radical feminist who penned the SCUM Manifesto, which Val quotes, and attempted to assassinate Andy Warhol.

Sonny (voiced by Paul Boocock): The paranoid hippie dog-owner of the group who is regularly tormented by Ted and Val. Ted has him addicted to an anti-psychotic medication he calls "Groovy Treats", as the medication is used to keep Sonny from hearing the voice of his dog Groovy. At some point in the past, Sonny and Groovy accidentally came across the Venture brothers, and in a paranoid psychotic rage killed the two. His and Ted's discovery of the boys alive and well lead the group to investigate further. Sonny is killed by Brock using Ted's gun, and is later turned into a new Venturestein under the original's command. He is a pastiche of Shaggy Rogers and David Berkowitz, the infamous "Son of Sam" serial killer who said he was coerced into his murders by a demon who spoke to him through a neighbor's dog.

Groovy (voiced by Christopher McCulloch): The gang's Great Dane who only seems to talk to Sonny in a German accent to push him into committing murder at the behest of "the Master", though Sonny had largely been able to resist him. No one else in the gang is ever spoken to by Groovy, so it is not clear if he can actually talk, as the Master is another character on The Venture Bros., or if the speech is a schizophrenic hallucination held by Sonny. At some point in the past, Sonny and Groovy found the Venture brothers and while Sonny bludgeoned one of them to death, Groovy fatally mauled the other. Groovy has his throat crushed by Venturestein and then turned into a shoe. He is a pastiche of Scooby-Doo and Harvey, the labrador retriever belonging to a neighbor of David Berkowitz who initially claimed that the dog had spoken to him, revealed he was a demon, and convinced Berkowitz to commit the murders.

The Outrider (voiced by Doc Hammer): Dr. Orpheus's former protege who successfully seduced Orpheus's wife and ended their marriage. Rather than focusing his attention on learning the ins and outs of necromancy, the Outrider spent his time looking at the easier shortcuts to achieve greater power, which included trepanning to insert an amulet known as the Eye of Osiris into his skull to provide him safe passage into and out of the Second World. He appears in "The Better Man", saving the Order of the Triad from an elder god Torrid summons from the Second World, but he later becomes trapped between worlds when attacked by Torrid once more. In their attempts to save him, the Order of the Triad removes the Eye of Osiris from his skull, trapping them in the Second World until Jefferson Twilight develops his latent magical abilities. The Outrider later admits he idolized Orpheus, but disliked how he attained his goals in life and found the easier way out, so that he would be able to be a family man. He and Tatyana teach Triana magic, and at Orpheus's Halloween party uses a puzzle box similar to the one from Hellraiser as part of their magical production that evening.

Tatyana: Dr. Orpheus's ex-wife and mother of Triana. When the Master uses her form to speak to Orpheus, he is entranced by its beauty and finds it difficult to teach Orpheus any sort of lesson, noting how buxom she is. It is only during this time that she speaks, but with the Master's voice. Tatyana bears a striking resemblance to Cassandra Peterson's horror hostess persona Elvira, Mistress of the Dark.

Brown Widow (voiced by Nathan Fillion): A superhero based in New York City who has the ability to spin webbing from his lower spine. He first appears in "Bright Lights, Dean City," in which he saves Dr. Venture using his powers when a taxi driven by Baron Underbheit goes out of control. He later appears to befriend Dean, revealing that he gained his powers (as well as multiple eyes on his forehead) in a laboratory accident involving spiders, though he quickly becomes more interested in singing a musical number with Dr. Venture. He later reappears in the sixth season as a college student and classmate of Dean, who does not seem to realize who he is. He is bullied by other students, who throw garbage at him to make him reflexively use his powers, which they believe is him soiling himself. In the past, he dated Sirena Ong, though they are no longer together, and he has a job at a ninja-themed restaurant. He is a parody of Spider-Man.

The Blue Morpho (voiced by Paul F. Tompkins): The Monarch's late father who was killed in a plane crash decades ago. His real name was Don Fitzcarraldo. He was initially presented as a socialite and good friend of Jonas Venture Sr., and later was revealed to have been a vigilante superhero affiliated with the original Team Venture. Kano was originally his bodyguard and crimefighting partner. He appeared on the Rusty Venture television show and had a comic book by Jack Kirby detailing his adventures published. However, much like Jonas, he had much poorer morals in private compared to his public persona; he engaged in such behaviors as cheating on his wife with celebrities, and didn't care if he was labeled a "bad guy" by the public. This embracing of the darker sides of his personality inspired his son to adopt the Blue Morpho mantle as his own, using the persona to eliminate rival supervillains for the right to arch Dr. Venture. He is eventually revealed to have been the Venture Industries hatchetman, eliminating any enemies Jonas might have had. In season 7 it is revealed he was resurrected by Jonas as the cyborg Venturion, who strangled young Rusty Venture and that led to Kano snapping his neck, killing him again. He is later found by Dr. Z who reconstructed him, which allowed him to become the former Councilman #1, Vendata. After regaining his memory, Venturion interfaces with Dr Jonas' and it is revealed that Jonas' blackmailed the Morpho by using a recording of Jonas, Morpho, Jill St. John and Stella Stevens in an orgy. The Morpho was very upset at this indiscretion because he and his wife have been trying for a child. Jonas agrees to "examine" his wife, claiming his science is very "potent." Venturion (regaining his human memory) calls Jonas out on this, but in true narcissist fashion Jonas shrugs it off. Regardless of Malcom's (The Monarch) biological father, The Morpho loved Malcom dearly, an emotion Jonas never authentically showed to his legitimate son Rusty. While Venturion is distracted recalling all the flashbacks, Jonas attempts to coerce Billy into switching their brains. Billy refuses to kill Venturion and The Monarch appears in Monarch fashion. Venturion sees him and joyfully mutters the name "Malcom," but before The Monarch can get any answers Jonas attacks him and through a series of event leads to the death of both. OSI later claims Jonas' head for "experiments." Morpho (along with his sidekick Kano) is a parody of The Green Hornet.

Sirena Ong: (voiced by Cristin Milioti) The daughter of Wide Wale (a possible play on Tobias Whale) and budding love interest of Hank. Because of her father's past mutation, she has inherited a number of whale-related physical traits, such as the need to regularly have her body in water and the ability to breathe underwater. She is blunt and temperamental, and although she understands her father's overbearing love for her, she is easily irritated by his henchmen when they try to keep her under control; she bears a particular dislike for one henchman named Rocco. She once dated Brown Widow prior to dating Hank, but broke up with him. Hank's good-natured efforts to impress her with the aid of Billy, Pete and Dean lead her to further develop deeper feelings for him because of how genuine he is. In Season 7, she and Hank are a couple now but she has to face her father's overprotectiveness and his lack approval in Hank. She also meets her uncle Douglas (Dugong) and is angry her father never told her about him. It is revealed in the mid-finale, she has cheated on Hank by sleeping with his brother Dean.

Sally Impossible (voiced by Mia Barron): Richard's estranged wife. She has invisible skin which leaves her muscle tissue visible (which is significantly less useful than the abilities of the Invisible Woman) and she requires all her concentration to keep her skin visible. This power is occasionally referred to as her becoming "visible" (making her "the visible woman").[6] She does not show any ability to create forcefields like her Marvel counterpart. Sally developed, and still maintains, a crush on Dr. Venture, who was repelled when he discovered her condition. Richard has implied that she has been repeatedly unfaithful and that her newborn son might have been fathered by someone else. This is a reference to the Invisible Woman's relationship with the Sub-Mariner, who has pursued her romantically from their first encounter. Eventually, it came to the point where Richard was keeping Sally practically as a prisoner in their home and keeping her under constant guard, accurately suspecting that she wanted to run away from him. Sally has been dating Jonas Venture Jr. and resides on Spider Skull Island with the rest of the Impossibles, sans Richard and Cody, though it is hinted that she and JJ are having troubles due to the latter's inability to commit. In "All this and Gargantua-2", however, her and JJ's strained relationship finally breaks and she decides to leave with Rocket and Richard, though she implies that her and Richard's relationship will be one of shared custody over Rocket rather than anything romantic or loving.

Rocket Impossible: Sally and Richard's newborn son. Thus far, he has not displayed any sort of super powers or genetic mutations. He is a parody of Franklin Richards, son of Mr. Fantastic and the Invisible Woman. Richard has previously voiced concerns that he may not be the father.

Ned (voiced by Christopher McCulloch): Sally and Cody's mentally handicapped cousin, who has been transformed into a "giant callus" with 3-inch-thick (76 mm) skin. He has a pale orange, lumpy appearance. He is stronger than ordinary people, but not nearly as strong or impervious to harm as the Thing. He lived with Sally, Rocket and J.J. on Spider-Skull Island for some time, but his whereabouts during the events of Gargantua-2 were unknown. He was later seen attending J.J.'s funeral with the rest of his family, including a reformed Richard.

Cody (voiced by Christopher McCulloch): Sally's brother. Bursts into flames when exposed to oxygen. Unlike the Human Torch, he cannot control this very painful reaction, so he is kept in an air-tight container. As a result, he is usually in a state of unconsciousness. In "Bright Lights, Dean City", Professor Impossible is revealed to have been using an imprisoned Cody to provide clean energy to Impossible Industries, an act which Phantom Limb describes as being "the most deliciously evil thing [he'd] ever seen", though the true evilness of it seems to be lost on Professor Impossible. His fate after being freed from Impossible Industries is unknown.

The Venture Bros. is, in part, a parody of Jonny Quest, and some Jonny Quest characters appear in several episodes; Cartoon Network and Warner Bros. own the rights to the Jonny Quest characters. Some of these characters, particularly Action Johnny, are drawn with variable line weights in the same style as the original comic-book-like Jonny Quest cartoons, as a visual homage.

Action Johnny/Jonny Quest (voiced by Brendon Small): Since the death of Dr. Benton Quest, he has been secreted away within the Quest Bathysphere, living in isolation and feeding (when possible) his addiction to narcotics, as shown in the episode "Twenty Years to Midnight". He is fooled into handing over a piece of Dr. Venture Sr.'s machinery after being bribed by the Captain and Jonas Jr. (who addresses him as "Mr. Quest," affirming his identity), an act that Jonas Jr. later regretted. He has sobered up, but is still a high strung nervous wreck due to his many psychological issues resulting from his father's irresponsible parenting. In "The Buddy System", Johnny claims that "fathers are caring and protective men, and I don't have one of those". In the same episode, Johnny also expresses the desire to free Dean from his father, but is stopped mid-sentence by Brock. He also implies that he staged several crimes to spite his father, including the murder of their dog Bandit. He has since shown to become much better in "Self Medication" as well as more functional and social, off-handedly mentioning that he had gone on a date with Velma Dinkley which resulted in him contracting herpes. In "The Terminus Mandate" it is revealed that he is living in a rehab facility, and he finally is able to make peace with Dr. Z.

Race Bannon (voiced by Christopher McCulloch): Brock's friend from the Office of Secret Intelligence, where he once worked as a torturer. Died after jumping from a jet that Nat King Cobra's Snake Men were piloting while retrieving the Goliath Serum. He carries various spy gadgets (all of them extremely dangerous) that are reminiscent of those carried by James Bond.

Hadji Singh (voiced by Jackson Publick): Another reference to a Jonny Quest character, he is now a manager working with Jonas Jr. He is seen also taking care of Johnny, while worrying that if he brings Johnny back home, his (Hadji's) wife will leave him.

Dr. Z (voiced by Christopher McCulloch): A reference to a recurring villain "Dr. Zin" in the Jonny Quest franchise, he was featured in the episode "The Buddy System" in which he was to be a special guest star in a stage show featuring Action Johnny. The show was being performed as part of "Rusty's Day Camp for Boy Adventurers." Upon seeing his old nemesis, Johnny panics and has a mental breakdown. Sergeant Hatred, having interrupted the show with what he thought was a routine arching, greets Zin with a hand shake, saying "The Dr. Z! Aw man, I love your work." In "Self-Medication" Dr. Z was confronted by Action Johnny, Dr. Venture, and a group of former "Boy Adventurers" to accuse him of the murder of their therapist. However, Dr. Z was innocent and the group discover that he is married. During a peaceful dinner Dr. Z advises the former "Boy Adventurers" that they need to grow up and stop living in the past, revealing that he feels that he had wasted his life and wished he and his wife could have had a normal marriage. In "Pomp and Circuitry", one of the silhouetted members of the Council of 13 looks and sounds a lot like Dr. Z. Appears to be a homage to Fu Manchu, an evil genius from a series of novels by English author Sax Rohmer. In "What Color is Your Cleansuit?" Dr. Z appears in an old Guild PSA to warn against the dangers of blundering henchmen. In "Bot Seeks Bot", Dr. Z is confirmed to be a member of the Council of 13. He is a member of the new Council of 13 in season 6, having survived the Sovereign's purge of the old Council.

Mrs. Z (voiced by Seth Green): Dr. Z's wife of many years after he retires from supervillainy. She says that she was in fact Dr. Z's beard until the two fell in love, although it was much too late to form a family.

Lance (voiced by Seth Green) and Dale Hale (voiced by John Hodgman): The Hale Brothers were previously famous boy detectives until the murder of their father, the reason for their therapy, particularly Dale who cannot get over the sight of seeing their father dead. It is hinted that they are the perpetrators, as Lance continually dismisses that their fingerprints were on the gun that was used to murder their father due to their sleuthing, and later, when Dr. Venture accuses them of doing so, Lance quips that it was never proven and Dale goes into hysterics believing that Dr. Venture knows the truth. It is implied that the murder was driven by Lance's desire to get at their inheritance, only to discover that their father's money would all go to the Boy Detective Academy, leaving them with nothing but a car to show for their crime, though they both cherish the vehicle. They are parodies of the Hardy Boys and The Menendez Brothers.

Ro-Boy Z (voiced by Christopher McCulloch): A robotic boy (loosely based on Astro Boy and MegaMan) who has abandonment issues due to his creator/father and psychopathic tendencies due to a life of fighting giant robots. He also has anger issues when he sees other robots, leading to apparent pyromaniacal tendencies. He eventually gets adopted by Dr. Z and his wife Mrs. Z, allowing the couple to fulfill their familial desires and giving Ro-Boy a way to move on from his creator.

A group of superheroes who also work as newscasters on the Action 5 News Team. They are a deconstruction of Silver Age superheroes.

Chuck Scarsdale/Captain Sunshine (voiced by Kevin Conroy): A sunlight-powered superhero previously mentioned by The Monarch in reference to having his henchmen return the charred remains of Wonder Boy to him. Captain Sunshine, appearing in person in the episode "Handsome Ransom", has since sworn revenge on The Monarch (whom he believes to be immune to his powers) and thwarts his plans to get a ransom for Hank and Dean from Dr. Venture when he takes Hank away, inducting him as his new sidekick and ward Wonder Boy. It is hinted that Captain Sunshine has pederastic tendencies towards the various boys he takes as his ward and Wonder Boy (which The Monarch attempts to exploit), although Jackson Publick has confirmed that this is not the case. In actuality, the various dangerous situations Scarsdale had to face as the original Wonderboy resulted in him developing an apparent case of Peter Pan syndrome, living out the childhood he never had through his colorful toy-filled mansion and living vicariously through his wards, who he does not train properly, resulting in the spectacular failure of both Wonderboy 2's solo career and Hank's attempt to fend off Henchman 21 (the "fight" ended with Hank down and crying after being punched once). Coupled with his guilt over the death of the 3rd Wonder Boy and his apparent habit of literally throwing criminals into prison (The Monarch describes this as his "usual" conduct) rather than handing them over to the authorities, Scarsdale is painted as a dangerously out-of-touch man in the vein of older superheroes (e.g. Superman and Captain Marvel). He is the lead anchor of the Action 5 News Team, but he leaves his post at the evening broadcast when The Monarch tries to re-kidnap Hank, despite being powerless at night. In the ensuing conflict, Captain Sunshine is exposed to a device Dr. Mrs. The Monarch created to reproduce his sun powers, intended to be his one weakness. Instead, the device repowers him and he rallies to defeat The Monarch and his minions, only to be disappointed when Hank chooses to step down as Wonder Boy and return home. In "Any Which Way But Zeus", Red Mantle claims he was not Captain Sunshine's archenemy, but the original Captain Sunshine (Desmond), identifying Scarsdale as the original Wonder Boy. In "Bot Seeks Bot", Sunshine and his new Wonderboy attend the funeral of his archenemy Boggles the Clue Clown and has an emotional outburst over the death of his long-time archenemy.

Desmond (voiced by Doc Hammer): Captain Sunshine's butler. In "Any Which Way But Zeus", Desmond is revealed to be the original Captain Sunshine, and Scarsdale his ward Wonder Boy. Desmond also acts as Zeus to convince the various organizations to set up a series of protective laws and such for sidekicks.

Wonderboy (voiced by Patton Oswalt): This former Wonderboy (legal issues prevent him from using the name) was the first ward of Captain Sunshine. As a result of his depression from being kicked out and his failed career as an independent hero (which is implied to have ended once he was sued for using the Wonderboy branding without permission), he has turned to binge eating and joins a support group of fellow former boy adventurers for therapy. It is assumed that he is the second Wonderboy, succeeding Scarsdale to Desmond, and preceding the one killed by The Monarch, Hank, and a fifth one who appears in season 5's "Bot Seeks Bot".

Wonderboy 5 (voiced by Larry Murphy): Captain Sunshine's current Wonderboy, who seems more or less indifferent to the death of Boggles the Clue Clown and has to drag Captain Sunshine away when he has an emotional outburst as Boggles' coffin is lowered into his grave. He also shows himself to be a more competent detective than his mentor, almost immediately solving Clue Clown's final riddle when Captain Sunshine was utterly stumped.

Barbara Qantas/Barbie-Q (voiced by Rachel Feinstein): Chuck Scarsdale's Australian co-anchor who as Barbie-Q resembles a Barbie doll that can spout pink flames. She is one of Zeus's captives in "Any Which Way But Zeus".

Sam Turgen/U.S. Steel (voiced by Doc Hammer): The Action 5 News Team's sports anchor who as U.S. Steel is a superpowered and Uncle Sam-inspired hero. In "Any Which Way But Zeus", U.S. Steel expects to find Ghost Robot, unaware he was killed earlier.

Neville Brown/Brown Thrasher: Sam Turgen's sports co-anchor who as Brown Thrasher has bird-themed powers akin to Falcon. He is one of Zeus's captives in "Any Which Way But Zeus".

Weatherbot 5/Ghost Robot (voiced by Christopher McCulloch): The Action 5 News Team's meteorologist whose true identity is that of a robot with a ghost inside of him. It is assumed he is killed by 21 during the events of season 4's "Any Which Way But Zeus" when 21 shatters his robotic eyes. However, in season 5's "Bot Seeks Bot", Ghost Robot is alive and well (owing to his being a robot with a ghost inside him), and he is deputized by the O.S.I. to aid in their undercover mission to discover the identities of the Council of Thirteen, by going on a date with Vendata as robotic Guild member Galacticon. Ghost Robot's interest in having fingers and the appearance of the real Galacticon jeopardize the mission, resulting in the death of Vendata.

The world's foremost scientific adventuring organization decades ago. It consisted of a group of extraordinary gentlemen led by the late, great, Jonas Venture. Although the present group is a less-than-worthy successor to the original team, they occasionally manage to have fantastic adventures nonetheless. In Now Museum-Now You Don't Jonas Venture Jr, mentions one of Dr. Venture's first missions was to stop the Rosenbergs, indicating the original Team Venture began in the early 1950s. As Dr. Venture died in the 1980s it is likely the original team ended then.

The Guild of Calamitous Intent

Organized super-villainy syndicate

A shadowy syndicate of major and minor supervillains, ne'er-do-wells, and otherwise outlandish criminals. The Guild has rules and guidelines regulating villainous behavior. Undercover Guild operatives are called "Strangers." The activities of Strangers are monitored by two Guild operatives (Watch and Ward), who receive orders from the mysterious entity, Sovereign and are ruled by the Council of 13 (all high-ranking Guild members). Currently operating without a "Sovereign" leadership, being ruled by committee by the Council, who no longer remain anonymous in an attempt of transparency following the actions of the previous Sovereign.

The loyal henchmen of The Monarch, who claims they prefer to be called "minions" rather than "henchmen". They are responsible for keeping the cocoon up and running as well as carrying out orders. They are armed with dart guns. The only henchmen that appear to continuously survive The Monarch's many botched attempts at killing Dr. Venture are Henchmen 21 and (until recently) 24.

The Order of the Triad

Adventuring

Dr. Orpheus' adventuring team recently approved for arching by the Guild of Calamitous Intent.

Office of Secret Intelligence

Secret spy organization

The supersecret spy organization of which Brock Samson was a member. According to agent Hunter Gathers, the O.S.I. has been in existence since "the second American Revolution—the invisible one". It trained him into the wonder he is today. Its name seems to be patterned after that of the real-life Office of Strategic Services, the precursor to the CIA or the Office of Scientific Intelligence, the controlling organization of The Six Million Dollar Man.

Its military outfits are vaguely reminiscent of those of S.H.I.E.L.D., but the dress code was discontinued in the 1980s, leading some members to choose flamboyant costumes. This is a deliberate reference to shows like G.I. Joe, where members of a military organization have highly individualized costumes as opposed to uniforms.

Impossible Industries

Scientific research and development

A scientific empire headed by Professor Richard Impossible. It includes a think tank in a secluded location near the North Pole and main headquarters in New York City. Pete White, Master Billy Quizboy, and Dr. Venture were selected to participate in an undisclosed project for the think tank. In the episode "20 Years to Midnight", several characters fall from a window in the New York City headquarters through a subway ventilation grate and directly into the path of an oncoming V train (on the F, V, B, D line) at which time a "5th Ave" sign is posted in the station. Based on this, the Impossible Industries headquarters is located across the street from/near the 53rd Street and 5th Avenue V station. It is also noted in "20 Years to Midnight" that the New York City headquarters was formerly a Venture Industries location.

Ünderland Troops

Forced military of Ünderland for former leader Baron Ünderbheit

Soldiers (formerly) at the service of Ünderland and Baron Ünderbheit. Seem to be proud of the discipline involved and unfazed by the fact they would be executed at age 38.

Conjectural Technologies

Business

A business started by Pete White and Master Billy Quizboy, operated out of the trailer in which they live. Dr. Venture contacted them to help identify and cure Dean's testicular torsion and enlisted their help in trying to fix his father's shrink ray to win a bet with Dr. Orpheus. The trailer also contains a hidden basement where the Billy and White perform their duties as the heroes Billy Quizboy and the Pink Pilgrim.

State University

School

A University which was attended by many of the series major characters, in two different time periods (Thaddeus Venture, Brock Samson, Pete White, Werner Ünderbheit, Mike Sorayama, and The Monarch during the early/mid eighties; Dr. Girlfriend, Billy Quizboy, and the future Sally Impossible during the late eighties/early nineties). Brock left to join the Army during his Freshman year, and several tragedies befell the others, but it is unknown if any of them graduated. Professor Hamilton Fantomos was employed there, until the accident which transformed him into Phantom Limb. Billy Quizboy attended for a few weeks, but only as a spy for O.S.I. who were looking into Fantomos. Professor Richard Impossible was also on the faculty, and shared an office with Fantomos, and taught at least one class attended by Thaddeus Venture. Impossible left the faculty shortly before Fantomos' accident, a result of a scandal involving his student Sally (later, his wife).

The Blackhearts Elimination Agency

Assassins Guild

An all-woman group of mercenary/assassins run by Molotov Cocktease. It is unknown whether it still exists.

The Soul Mates

Adventurers/Youth ministry

After leaving the OSI, Shore Leave and Mile High assumed new identities (Holy Diver and Sky Pilot) and started the "fastest growing youth ministry in southern California", The Action Bible School. They referred to their duo as "the Soul Mates". This group is now defunct, as both members joined S.P.H.I.N.X.

S.P.H.I.N.X.

Independent Secret Spy/Peacekeeping Organisation

Originally a terrorist organisation that drew many parallels with Cobra Command, it was shut down by the O.S.I. and later revived by disgruntled former O.S.I. agents who disliked the system set up with the Guild of Calamitous Intent. The organisation currently exists in secret, hunting down international threats who have not signed up with the Guild and thus are beyond the O.S.I.'s power. Agents known thus far are its leader, Col. Hunter Gathers, his protégé Brock Samson, former operatives Shore Leave and Mile High, and an unnamed German plastic surgeon. They currently maintain a secret base hidden inside the Venture Compound. 21 joined the group during "Operation PROM". Hunter was made head of OSI in the same episode he reinstated Brock and the others leaving 21 the only member of S.P.H.I.N.X. In "S.P.H.I.N.X. Rising", Gary (under name Viceroy) working as a member of S.P.H.I.N.X. and continues its mission of targeting unregistered supervillains, but ends up foiling an OSI undercover operation involving Shoreleave and Brock. He eventually decides on recruiting ex-villains and henchman who want to be heroes. Hank decides to join in on the action and claims the powersuit of former S.P.H.I.N.X. second-in-command The Countess for himself. Three others respond to his ad, and turn out to be original S.P.H.I.N.X. members (S.P.H.I.N.X. Commander, Windsong, & Diamondbackdraft). They join in order to reclaim their organization from Gary. The original S.P.H.I.N.X. is defeated by Brock and Shoreleave. Col. Hunter Gathers then destroys the S.P.H.I.N.X. hoverfortress and S.P.H.I.N.X. base at the Venture Compound is mistakenly destroyed by The Monarch due to Sgt Hatred's intervention. Both incarnations of S.P.H.I.N.X. are no defunct and no longer active.

The Revenge Society

Independent Villain Group

Formed by Phantom Limb, and named after his alternate codename–Revenge–the first incarnation consisted of himself, Billy Quizboy, Guild Councilmen 3 & 8 (all of whom he had kidnapped and forced into service), as well as three inanimate objects which Phantom Limb believed to be alive. After freeing himself from guild incarceration, Phantom Limb formed a second version of the Society with Professor Impossible, Baron Werner Ünderbheit, Fat Chance, and Lady Bird and Lyndon Bee (characters based on the fantasy film Ladyhawke and American President Lyndon Johnson and his wife). The third and final iteration lost Bird and Bee and saw them replaced with Radical Left and (henchman) Zero, now overseen by Killinger to train them to be a crack villain team. Ultimately absorbed into the new Guild of Calamitous Intent following the Sovereign's betrayal, losing Professor Impossible (defected to ex-wife to help raise son), Ünderbheit, Fat Chance (presumed dead aboard Gargantua-2) and Zero (definitely dead). Revealed to be a long game by Killinger to reestablish the Council of 13, having presumably foreseen the Sovereign's doublecross (and Phantom Limb's inner desire to return to the Guild), with the remaining members becoming part of the new Council.

The Brimstone Assembly

Gathering of Magic Users

Occasional gathering of magic users and mystics which includes Doctor Orpheus, the Outrider, Orpheus' ex-wife, the Alchemist, and Red Mantle. Outsiders are usually not allowed to come to gatherings but Red Mantle had to bring Dragoon to the 331st meeting due to them sharing a body. The Master has apparently trained many of them and appeared at the 331st meeting after the group summoned a zombie army from the Potter's Field near the Venture Compound.

Crusaders Action League

For-Profit Confederation of Super Heroes

An organization of superheroes in New York City that ostensibly exists to provide protection plans for the city's super-scientists, consisting of (at least) Stars and Garters, Fallen Archer, Warriana and Night Dick. It is however revealed to be a shakedown operation controlled by Wide Wale.